an investigation into the factors that govern …

The Pennsylvania State University

The Graduate School

AN INVESTIGATION INTO THE FACTORS THAT GOVERN SUCCESS

FOR NEW SAFETY AND HEALTH TECHNOLOGIES IN THE MINING INDUSTRY

AND THE EFFICACY OF THOSE FACTORS TO PREDICT THE LIKELIHOOD

OF SUCCESS FOR EMERGING TECHNOLOGIES

A Dissertation in

Energy and Mineral Engineering

by

Jacob L. Carr

© 2019 Jacob L. Carr

Submitted in Partial Fulfillment

of the Requirements

for the Degree of

Doctor of Philosophy

December 2019

ii

The dissertation of Jacob L. Carr was reviewed and approved* by the following:

Jeffrey L. Kohler

Professor of Mining Engineering

Undergraduate Program Chair of Mining Engineering

Dissertation Adviser

Chair of Committee

Shimin Liu

Associate Professor of Energy and Mineral Engineering

Sekhar Battacharyya

Associate Professor of Mining Engineering

Michael Pate

Nationwide Insurance Associate Professor of Agricultural Safety and Health

Mort D. Webster

Professor of Energy Engineering

Co-Director Initiative for Sustainable Electric Power Systems

Associate Department Head for Graduate Education

*Signatures are on file in the Graduate School.

iii

Abstract The mining industry faces many safety and health challenges, and these challenges are often

addressed by the introduction of new technologies, many of which are introduced through

legislative or regulatory mandates requiring the technology’s use. Many such mandates have been

enacted, causing dramatic changes to how work is conducted. Despite these mandates, there are

cases in which the intended safety or health benefit of introducing a new technology was not

achieved, or worse, cases in which some unintended negative consequence was created by the

introduction of a new technology. Given the weighty consequences these mandates can have, both

in terms of economic impacts as well as impacts on the safety and health of miners, it is

increasingly critical to ensure that the technologies being mandated will achieve their intended

benefit without introducing unintended negative consequences. To that end, the goal of the

research presented in this dissertation was to identify the factors that govern the success of new

safety and health technologies in the mining industry and to develop guidance for the timely and

effective introduction of new safety and health technologies through legislative or regulatory

mandates. This goal was accomplished through an analysis of several case studies of mining safety

and health technology introduction, including mandated as well as voluntarily adopted

interventions. For each case study, the development and diffusion of the technology was examined

and indications that the technology achieved either a successful or an unsuccessful outcome was

identified. Causal tree analysis was then used to identify the root causes for each of these successful

and unsuccessful outcomes. The root causes identified for unsuccessful outcomes include, among

other factors, the effect of biases on decisions made by researchers, regulators, and legislators. The

analysis shows that these root causes lead to consequences including the failure of interventions

to deliver their intended safety or health benefit or for new interventions to introduce unintended

negative safety consequences. Using these root causes, a bowtie analysis was conducted to identify

controls for preventing the enactment of legislative or regulatory mandates requiring the use of

immature technologies and to mitigate the negative consequences of the enactment of such a

mandate. These controls represent a set of guidelines that can be used to ensure that immature

safety and health technologies are not introduced prematurely and that future mining safety and

health regulations and legislation are as effective as possible at protecting the safety and health of

miners. The implementation of these guidelines will result in more effective regulation, more

impactful safety and health research, safer mines, and healthier miners.

iv

Table of Contents List of Figures ............................................................................................................................... vii

List of Tables ................................................................................................................................. xi

Acronyms and Abbreviations ...................................................................................................... xiv

Chapter 1: Introduction ....................................................................................................................1

Objectives and Specific Aims ......................................................................................................4

Scope of Work .............................................................................................................................5

Dissertation Format ......................................................................................................................6

Chapter 2: Background and Survey of Pertinent Literature.............................................................8

2.1 The Economics of Technological Change .............................................................................8

2.2 The Effect of Policy on Technological Change ...................................................................11

2.3 The Assessment of Environmental Control Technologies ...................................................12

2.4 The Assessment of Technology Readiness ..........................................................................13

Chapter 3: Methodology ................................................................................................................16

3.1 Overall Research Approach .................................................................................................16

3.2 Data Compilation and Consultation with Subject Matter Experts .......................................18

3.3 Identification of Factors that Influence the Success of New Safety and Health

Technologies ..............................................................................................................................19

3.4 Development of Strategies to Improve the Likelihood of Success for New Safety

and Health Technology Mandates .............................................................................................20

Chapter 4: Case Studies of Safety And Health Technology Introduction to the Mining

Industry ..........................................................................................................................................24

4.1 Safety Interventions .............................................................................................................25

4.1.1: Case 1: Refuge Alternatives for Use in Underground Coal Mines..............................25

4.1.2 Case 2: Self-Contained Self-Rescuers ..........................................................................37

4.1.3 Case 3: Primary Communications and Tracking Systems ............................................48

v

4.1.4 Case 4: Proximity Detection Systems for Continuous Mining Machines ....................68

4.1.5 Case 5: LED Cap Lamps...............................................................................................72

4.2 Health Interventions .............................................................................................................81

4.2.1 Noise Controls and Noise Exposure Regulations .........................................................82

4.2.2 Case 6: Noise Controls for Continuous Mining Machines ...........................................88

4.2.3 Case 7: Noise Controls for Roof Bolting Machines .....................................................96

Chapter 5: Causal Tree Analyses .................................................................................................101

5.1 Causal Tree Analyses for Safety Interventions ..................................................................103

5.1.1 Causal Tree Analysis for Case 1: Refuge Alternatives ...............................................103

5.1.2 Causal Tree Analysis for Case 2: Self-Contained Self-Rescuers ...............................118

5.1.3 Causal Tree Analysis for Case 3: Primary Communications and Tracking

Systems ................................................................................................................................126

5.1.4 Causal Tree Analysis for Case 4: Proximity Detection Systems ................................141

5.1.5 Causal Tree Analysis for Case 5: LED Cap Lamps ....................................................144

5.2 Causal Tree Analyses for Health Interventions .................................................................146

5.2.1 Causal Tree Analysis for Noise Controls for Case 6: Continuous Mining

Machines ..............................................................................................................................146

5.2.2 Causal Tree Analysis for Noise Controls for Case 7: Roof Bolting Machines ..........151

5.3 Generalization of Causal Tree Analysis Results ................................................................155

Chapter 6: Bowtie Analysis of Mandates for Immature Safety and Health Technologies ..........164

6.1 Threats and Outcomes Associated with the Enactment of a Mandate for an

Immature Safety or Health Technology ...................................................................................165

6.2 Overview of Bowtie Analysis ............................................................................................169

6.3 Discussion of Controls to Prevent the Enactment of a Mandate for an Immature

Safety or Health Technology ...................................................................................................171

6.3.1: (T1) Biases lead legislators to judge that immediate action is needed and to

ignore indications of technology immaturity .......................................................................172

vi

6.3.2: (T2) Biases lead regulators to judge that immediate action is needed and to

ignore indications of technological immaturity ...................................................................175

6.3.3: (T3) Biases and political pressures lead researchers to ignore or to understate

observed indications of technological immaturity ...............................................................179

6.3.4: (T4) Despite the best efforts of researchers and developers, effective

interventions either cannot be developed or cannot be demonstrated to be effective

due to engineering challenges or economic constraints .......................................................181

6.3.5: (T5) Biases lead to an acceptance of the status quo with respect to recognized

deficiencies in safety and health standards or technologies.................................................184

6.3.6: (T6) Cultural forces and cognitive biases among miners lead to a mistrust of

new interventions .................................................................................................................188

6.3.7: (T7) Biases result in insufficient or poorly designed experiments and (T8)

Biases result in insufficient or ineffective review of research .............................................189

6.4 Discussion of Controls to Mitigate the Enactment of a Mandate for an Immature

Safety or Health Technology ...................................................................................................198

6.4.1: (C1) Intervention does not achieve the intended safety or health benefit .................199

6.4.2: (C2) Intervention causes an unintended, negative safety or health consequence ......203

6.4.3: (C3) A device that fails to meet the safety and health standard or is otherwise

defective is certified and used ..............................................................................................204

6.4.4: (C4) Despite effective interventions being available to meet the mandate,

there is sustained strong resistance to their use ...................................................................205

Chapter 7: Guidelines and Recommendations to Improve the Likelihood of Success for

New Safety and Health Technology Mandates ............................................................................208

7.1 Summary of Recommendations .....................................................................................208

7.2 Implementation of Policies to Assess Technology Maturity .........................................210

Chapter 8: Conclusions and Recommendations ..........................................................................229

References ....................................................................................................................................240

vii

List of Figures

Figure 1: Generic Causal Tree Analysis Framework .....................................................................19

Figure 2: Generic bow-tie analysis framework ..............................................................................20

Figure 3: Bow-tie analysis framework as applied in the proposed research ..................................21

Figure 4: Metal-type portable refuge alternative ...........................................................................25

Figure 5: A tent-type portable refuge alternative deployed in the Experimental Mine at

the NIOSH facility in Pittsburgh............................................................................26

Figure 6: Door to a built-in-place refuge alternative constructed in the Experimental Mine

at the NIOSH facility in Pittsburgh ........................................................................26

Figure 7: CSE SR-100 Self-Contained Self-Rescuer ....................................................................38

Figure 8: Leaky feeder cable..........................................................................................................49

Figure 9: Conceptual drawing of node-based communications .....................................................50

Figure 10: Tag-based tracking concept ..........................................................................................52

Figure 11: Tracking tag used in underground coal mines..............................................................52

Figure 12: Miners' cap lamp assembly from the early 20th century with spring-loaded

contacts designed to interupt electric current in the event that the

incandescent bulb shattered [174] ..........................................................................73

Figure 13: The Edison Electric Cap Lamp, approved by the Bureau of Mines for use in

underground coal mines in 1915 [176] ..................................................................74

Figure 14: Single sprocket chain conveyor on a continuous mining machine (Source:

[228])......................................................................................................................89

Figure 15: Dual sprocket chain conveyor on a continuous mining machine (Source:

[228])......................................................................................................................89

Figure 16: Dual sprocket conveyor chain with polyurethane-coated flight bars on a

continuous mining machine (Source: [228])..........................................................89

Figure 17: Average noise dose for continuous mining machine operators as reported in

the MSHA Noise Samples data set [217] ..............................................................94

Figure 18: Proportion of noise surveys for continuous mining machine operators for

which the PEL dose was above 100% as reported in the MSHA Noise

Samples data set [217] ...........................................................................................94

viii

Figure 19: Average noise dose for roof bolting machine operators as reported in the

MSHA Noise Samples data set [217] ..................................................................100

Figure 20: Proportion of noise surveys for roof bolting machine operators for which the

PEL dose was above 100% as reported in the MSHA Noise Samples data

set [217]. ..............................................................................................................100

Figure 21: Causal tree analysis for “Judicial intervention and after-rule time extensions

occurred in refuge alternatives rulemaking” (See notes in Table 12) ..................105

Figure 22: Causal tree analysis for “Miners express strong resistance to using refuge

alternatives” (portions shown in dashed lines are not shown in their

entirety because they would duplicate portions of Figure 21; therefore,

only the root causes are shown) ...........................................................................115

Figure 23: Causal tree analysis for "Unacceptably high rate of quality control failures

occur for CSE SR-100 self-contained self-rescuers" (See notes in Table

15) ........................................................................................................................119

Figure 24: Causal tree analysis for "Primary communications and tracking systems are

adopted throughout the underground coal mining industry" (See notes in

Table 17) ..............................................................................................................128

Figure 25: Causal tree analysis for "No documented evidence exists showing that

tracking systems achieve a material improvement to safety" (See

remainders of causal tree in Figure 26 and Figure 27) ........................................134

Figure 26: Causal tree analysis for "Compelling evidence does not exist to indicate that

the performance standards, if achieved, will substantially improve the

likelihood of successful rescue or escape" (Continues from Figure 25; see

notes in Table 19).................................................................................................135

Figure 27: Causal tree analysis for "Compelling evidence does not exist to indicate that

the tracking systems in use in the industry meet the performance

standards" (Continues from Figure 25) ................................................................136

Figure 28: Causal tree analysis for "Electromagnetic interference (EMI) between

continuous personal dust monitors and proximity detection systems

effectively render the proximity detection system temporarily inoperable" ........141

Figure 29: Causal tree analysis for "LED cap lamps are rapidly and voluntarily adopted

by mine operators throughout the underground mining industry" .......................145

Figure 30: Causal tree analysis for "Continuous mining machine noise controls achieve a

demonstrated reduction in noise exposure for operators" (See notes in

Table 23) ..............................................................................................................147

ix

Figure 31: Causal tree analysis for "Roof bolting machine noise controls fail to achieve a

demonstrated reduction in noise exposure for operators" (See notes in

Table 25) ..............................................................................................................152

Figure 32: Threats contributing to the enactment of a law or regulation that mandates the

use of a safety or health technology that is immature ..........................................168

Figure 33: Bowtie analysis of the enactment of a law or regulation that mandates the use

of a safety or health technology that is immature ................................................170

Figure 34: Left-hand side of bowtie analysis of the enactment of a law or regulation that

mandates the use of a safety or health technology that is immature,

showing threats and preventative controls ...........................................................171

Figure 35: Partial bowtie analysis of the enactment of a law or regulation that mandates

the use of a safety or health technology that is immature, showing portion

associated with Threat 1.......................................................................................173






















Figure 43: Five-stage process of research and reviews associated with each stage ....................193

x

Figure 44: Right-hand side of bowtie analysis of the enactment of a law or regulation that

mandates the use of a safety or health technology that is immature,

showing consequences and recovery controls .....................................................198



associated with Consequence 1 ............................................................................200










Figure 49: Technology Readiness Levels as defined by NASA [257] ........................................212

Figure 50: Sources of uncertainty about technology's readiness at each TRL ............................223

Figure 51: Risk of unsuccessful outcomes decreases with increasing TRL; relative level

of risk for each type of unsuccessful outcome is indicated by the width of

the column, which decreases with increasing TRL .............................................225

Figure 52: Recommended TRL definitions for mining safety and health technologies ..............238

xi

List of Tables

Table 1: Summary of key guidance provided by MSHA for communications system

performance [128] ..................................................................................................61

Table 2: Summary of key guidance provided by MSHA for tracking system performance

[128] .......................................................................................................................62

Table 3: NIOSH OMSHR extramural research contracts in the topic area “Emergency

Communications and Tracking” (2006 - 2016) [134]............................................64

Table 4: Key dates for proximity detection regulations .................................................................70

Table 5: Estimated excess risk of material hearing impairment at age 60 after a 40-year

working lifetime exposure to occupational noise for different definitions

of material hearing impairment (From [212]) ........................................................84

Table 6: Engineering and administrative noise controls considered by MSHA to be

technologically and administratively achievable in reducing the noise

exposure of miners operating or working around continuous mining

machines [229] .......................................................................................................91

Table 7: Engineering and administrative noise controls considered by MSHA to offer

promise in reducing the noise exposure of miners operating or working

around continuous mining machines [24] ..............................................................92

Table 8: Engineering and administrative noise controls considered by MSHA to be

technologically and administratively achievable in reducing the noise

exposure of miners operating or working around roof bolters [229] .....................98

Table 9: Engineering and administrative noise controls considered by MSHA to offer

promise in reducing the noise exposure of miners operating or working

around roof bolters [24] .........................................................................................98

Table 10: Indicators of a successful safety and health technology introduction .........................102

Table 11: Indicators of an unsuccessful safety and health technology introduction ...................102

Table 12: Notes for causal tree analysis for “Judicial intervention and after-rule time

extensions occurred in refuge alternatives rulemaking” (See causal tree in

Figure 21) .............................................................................................................106

Table 13: Identified root causes for “Judicial intervention and after-rule time extensions

occurred in refuge alternatives rulemaking” ........................................................113

Table 14: Identified root causes for “Miners express strong resistance to using refuge

alternatives” .........................................................................................................117

xii

Table 15: Notes for causal tree analysis for "Unacceptably high rate of quality control

failures occur for CSE SR-100 self-contained self-rescuers" (See causal

tree in Figure 23) ..................................................................................................120

Table 16: Identified root causes for "Unacceptably high rate of quality control failures

occur for CSE SR-100 self-contained self-rescuers" ...........................................126

Table 17: Notes for causal tree analysis for "Primary communications and tracking

systems are adopted throughout the underground coal mining industry"

(See causal tree in Figure 24) ...............................................................................129

Table 18: Identified root causes for "Primary communications and tracking systems are

adopted throughout the underground coal mining industry" ...............................133

Table 19: Notes for causal tree analysis for "No documented evidence exists showing that

tracking systems achieve a material improvement to safety" (See causal

trees in Figure 25, Figure 26, and Figure 27) ......................................................137

Table 20: Identified root causes for "No documented evidence exists showing that

tracking systems achieve a material improvement to safety" ..............................140

Table 21: Identified root causes for "Electromagnetic interference (EMI) between

continuous personal dust monitors and proximity detection systems

effectively render the proximity detection system temporarily inoperable" ........144

Table 22: Identified root causes for "LED cap lamps are rapidly and voluntarily adopted

by mine operators throughout the underground mining industry" .......................145

Table 23: Notes for causal tree analysis for "Continuous mining machine noise controls

achieve a demonstrated reduction in noise exposure for operators" (See

causal tree in Figure 30) .......................................................................................148

Table 24: Identified root causes for "Continuous mining machine noise controls achieve a

demonstrated reduction in noise exposure for operators" ....................................151

Table 25: Notes for causal tree analysis for "Roof bolting machine noise controls fail to

achieve a demonstrated reduction in noise exposure for operators" (See

causal tree in Figure 31) .......................................................................................152

Table 26: Identified root causes for "Roof bolting machine noise controls fail to achieve a

demonstrated reduction in noise exposure for operators" ....................................154

Table 27: Identified root causes for indications of safety and health technology mandate

success..................................................................................................................155

Table 28: Identified root causes for indications of safety and health technology mandate

failure ...................................................................................................................156

xiii

Table 29: Root causes for indications of technology mandate success grouped by groups

primarily involved ................................................................................................158

Table 30: Root causes for indications of technology mandate failure grouped by groups

primarily involved ................................................................................................159

Table 31: Summary of recommended preventative and recovery controls to prevent and

mitigate, respectively, the enactment of a legislative or regulatory mandate

for the use of an immature safety or health technology .......................................209

Table 32: TRL definitions used by NASA and DOD as well as a suggested set of

definitions for mining safety and health technologies (These scales are

identical for TRL 1 through 5 but have minor differences for TRL 6

through 9) .............................................................................................................213

Table 33: Guidance for adjusting TRL for a technology that has been developed for and

tested in some prior environment and is being adapted to a new

environment .........................................................................................................215

Table 34: Effects on federal and state legislative bodies of assessing the readiness of

safety and health technologies .............................................................................218

Table 35: Effects on regulatory agencies of assessing the readiness of safety and health

technologies .........................................................................................................219

Table 36: Effects on research agencies of assessing the readiness of safety and health

technologies .........................................................................................................220

Table 37: Effects on the mining industry of assessing the readiness of safety and health

technologies .........................................................................................................221

Table 38: Generalized forms of identified root causes for successful outcomes in case

studies of safety and health technology introductions studied.............................232

Table 39: Generalized forms of identified root causes for unsuccessful outcomes in case

studies of safety and health technology introductions studied.............................233

xiv

Acronyms and Abbreviations

Organizations:

CDC .......................................Centers for Disease Control and Prevention

CSE ........................................Refers to the CSE Corporation

DART .....................................Division of Applied Research and Technology

DHHS .....................................Department of Health and Human Services

DOD .......................................Department of Defense

DOE .......................................Department of Energy

DOL .......................................Department of Labor

EPA ........................................Environmental Protection Agency

ESA ........................................European Space Agency

GAO .......................................Government Accountability Office

ISO .........................................International Organization for Standardization

MESA ....................................Mine Enforcement and Safety Administration

MSA .......................................Mine Safety Appliances Company

MSHA ....................................Mine Safety and Health Administration

MSHRAC ...............................Mine Safety and Health Research Advisory Committee

MSTTC ..................................Mine Safety Technology and Training Commission

NAS........................................National Academy of Sciences

NASA .....................................National Aeronautics and Space Administration

NIOSH ...................................National Institute for Occupational Safety and Health

NMA ......................................National Mining Association

NPPTL ...................................National Personal Protective Technology Laboratory

OMB ......................................Office of Management and Budget

OMSHR .................................Office of Mine Safety and Health Research

OSHA .....................................Occupational Safety and Health Administration

PMRD ....................................Pittsburgh Mining Research Division

PRL ........................................Pittsburgh Research Laboratory

SMRD ....................................Spokane Mining Research Division

USBM ....................................United States Bureau of Mines

WVMSTTF ............................West Virginia Mine Safety Technology Task Force

xv

Other Acronyms and Abbreviations:

ANPRM .................................Advance Notice of Proposed Rulemaking

APA........................................Administrative Procedure Act

AT ..........................................Apparent Temperature

BACT .....................................Best Available Control Technology

BIP .........................................Built-in-place (referring to a refuge alternative)

CDEM ....................................Coal Dust Explosibility Meter

CFR ........................................Code of Federal Regulations

CO ..........................................Carbon Monoxide

CO2 .........................................Carbon Dioxide

CPDM ....................................Continuous Personal Dust Monitor

EMC .......................................Electromagnetic Compatibility

EMI ........................................Electromagnetic Interference

ERP ........................................Emergency Response Plan

FACA .....................................Federal Advisory Committee Act

GNSS .....................................Global Navigation Satellite System

GPS ........................................Global Positioning System

HCP ........................................Hearing Conservation Plan

HTL ........................................Hearing Threshold Level

IRB .........................................Institutional Review Board

LAER .....................................Lowest Achievable Emissions Rate

LAN .......................................Local Area Network

LED ........................................Light-Emitting Diode

LIDAR ...................................Light Detection and Ranging

LiOH ......................................Lithium Hydroxide

LTFE ......................................Long Term Field Evaluation

MEMS ....................................MicroElectro-Mechanical Systems

MF ..........................................Medium Frequency

MINER ...................................Mine Improvement and New Emergency Response

MSD .......................................Musculoskeletal Disorders

MWC......................................Miner-Wearable Component

NFC ........................................Near-Field Communication

xvi

NLOS .....................................Non-Line-Of-Sight

NPRM ....................................Notice of Proposed Rule Making

O2 ...........................................Oxygen

PAN........................................Personal Area Network

PDM .......................................Personal Dust Monitor

PDS ........................................Proximity Detection System

PEL ........................................Permissible Exposure Limit

PIB .........................................Program Information Bulletin

PIL..........................................Program Instruction Letter

PPL .........................................Program Policy Letter

PRA ........................................Paperwork Reduction Act

QA ..........................................Quality Assurance

R&D .......................................Research and Development

RA ..........................................Refuge Alternative

RACT .....................................Reasonably Available Control Technology

RBLC .....................................RACT/BACT/LAER Clearinghouse

RADAR..................................Radio Detection and Ranging

REL ........................................Recommended Exposure Limit

RFI .........................................Request for Information

RSSI .......................................Received Signal Strength Indicator

RFID ......................................Radio Frequency Identification

SCSR ......................................Self-Contained Self-Rescuer

SEC ........................................Self-Escape Competencies

SME .......................................Subject Matter Expert

TPMM ....................................Technology Program Management Model

TOF ........................................Time of Flight

TRA........................................Technology Readiness Assessment

TRL ........................................Technology Readiness Level

TRLC .....................................Technology Readiness Level Calculator

TTE ........................................Through-the-Earth

TWA ......................................Time-Weighted Average

UWB ......................................Ultra-Wideband

1

Chapter 1: Introduction

Mineworkers face some of the most challenging safety and health risks of any industry. Miners

work near heavy pieces of machinery and often work in confined spaces. Miners also work in

low light conditions and often have high exposures to noise as well as to dust and other

respiratory hazards. And miners face the risk of disastrous explosions, fires, or falls of ground

that can trap them underground. To address these risks, several technologies have been

introduced to the mining industry with the intent of protecting miners’ safety and health.

The Coal Mine Safety Act of 1969 (Coal Act), precipitated by the Farmington Mine disaster in

1968, instituted many new safety and health requirements and led to the introduction of many

new technologies to the mining industry. These requirements were later extended to non-coal

mines by the Federal Mine Safety and Health Act of 1977 (Mine Act).

December of this year will mark the 50th anniversary of the passage of the Coal Act. In this half-

century, conditions at mines have steadily improved, as evidenced by dramatic decreases in the

rates of injuries, fatalities, and occupational illness. This improvement has been driven largely by

the promulgation of important regulations and the introduction of several new safety and health

technologies. However, despite these improvements, significant safety challenges remain for the

industry.

In 2006, disasters at the Sago, Darby, and Alma mines led to the passage of the Mine

Improvement and New Emergency Response (MINER) Act of 2006. The MINER Act

dramatically expanded the requirements of the Coal and Mine Acts by mandating the

implementation of new technologies such as communications and tracking systems, refuge

alternatives, and breathing air supply systems. In addition to the new requirements of the MINER

2

Act, mining safety and health requirements have increased over the last decade with new

regulations mandating the use of technologies such as proximity detection and personal dust

monitors. Still other technologies, such as LED cap lamps, have been voluntarily adopted within

the industry without government mandate. In a few instances the improved understanding of

health hazards, such as diesel particulate matter, have led to a recognition of the need for

technological solutions. New safety and health technologies can either be developed within and

specifically for the mining industry, or can be adopted and adapted from other industries.

These technologies are sometimes voluntarily adopted by the industry, but more often, they are

widely adopted only after a mandate requiring their use is enacted, either through legislation or

regulation. A recent examination of safety and health advances in the mining industry over the

last several decades provides some perspective on how new safety and health technologies have

been adopted by the industry [1]. For several cases, a new technology was developed and

voluntarily adopted by some portion of the industry, but a regulatory or legislative mandate was

required to achieve pervasive use. For example, the use of rock dust to prevent deadly mine

explosions was adopted by some mines in the 1930s, and rock dust was used in the majority of

mines by 1940. However, it was not used in all mines until required by the 1952 Federal Coal

Mine Safety Act.

In other cases, legislative or regulatory mandates completely precede the development and use of

the technology. For example, the MINER Act mandated the use of wireless communications and

tracking systems for underground coal mines, but, at the time this law was passed, the

technology did not exist in a mature form for use by the industry. Such requirements are referred

to as “technology-forcing” mandates as they are designed to force the development and diffusion

of technologies that do not yet exist. In the case of the MINER Act, the legislation drove

3

research and development of new technologies by their use, by charging federal research

agencies with the responsibility of spearheading research and development efforts, and by

funding those efforts. As with all safety and health technology mandates, the intent of the

MINER Act was to improve safety and health through the introduction of new technologies.

While the intent of regulatory or legislative mandates is to improve the safety and health of

miners, this intent is sometimes not fully achieved because the mandated technology fails to

deliver the expected benefit. Worse, the introduction of a new technology can sometimes cause

unintended and unexpected consequences that have a negative impact on safety and health. As

new technologies continue to be developed and introduced – whether through mandate or

through voluntary adoption – it will be increasingly critical to understand why some safety and

health technologies achieve success, while others fail to do so. The goal of the research presented

in this dissertation is to provide this understanding by identifying the factors that have driven

some safety and health technologies to success and prevented others from reaching success.

From these factors, a set of guidelines is presented that can be used to inform the development of

future safety and health regulations, to steer the strategic direction of safety and health research,

and to ensure that the introduction of new technologies will achieve their intended benefit

without introducing some unintended negative consequence.

The guidelines provided in this dissertation build on a deep body of knowledge on the

mechanisms by which technology is developed and diffused as well as how those mechanisms

can be impacted by laws and regulations. Notably, much has been done by federal agencies such

as NASA, the Department of Defense, and the Department of Energy, to assess the readiness of

technology for deployment through Technology Readiness Levels. The results of this study

demonstrate the applicability of these tools, with some modification, to mining safety and health

4

technology assessment. The results also demonstrate the need for rigorous scientific assessment

of safety and health interventions to overcome the effects of biases and maintain objectivity in

the regulatory, legislative, and research processes.

By identifying the factors that govern the success of new safety and health technology

introduction in the mining industry, this research fills a critical knowledge gap, and by

translating these findings into actionable guidelines, this dissertation provides the mining

community with a valuable set of tools for ensuring that future safety and health technology

introduction efforts achieve success. The implementation of these guidelines will enable the

design of effective regulations, which are backed by sound science and which mandate the use of

technologies that have been proven to be sufficiently mature. In this way, the use of the

information presented in this dissertation will minimize the regulatory burden of new mining

safety and health requirements while providing the most effective and proven protections for

miners’ safety and health.

Objectives and Specific Aims

The research addresses the following objectives:

Objective 1: Test the hypothesis that there exists some set of factors that govern the

success of mandated safety and health technologies in the mining industry

and that these factors can be determined.

Objective 2: Establish a set of guidelines to maximize the likelihood of success for new

safety and health technologies that may be mandated for the mining

industry.

5

These objectives have been accomplished through the achievement of three specific aims:

Specific Aim 1: Identify factors or conditions that have positively contributed to the

success of safety and health technologies in mining.

Specific Aim 2: Identify factors or conditions that have negatively affected the success of

safety and health technologies in mining.

Specific Aim 3: Develop a set of strategies to: (a) reduce the likelihood of a government

mandate being enacted for an immature safety or health technology, and

(b) mitigate the repercussions of the enactment of a mandate for an

immature safety or health technologies.

Scope of Work

The factors identified and the guidelines developed in this research are applicable to all sectors

of mining, including both surface and underground mines as well as all mining commodities:

coal, metal, non-metal, stone, sand and gravel. However, due to the unique nature and heightened

safety concerns of underground coal mining, this sector has seen a disproportionately large

number of mandated technologies as compared to the other sectors. Therefore, the data used for

this study has necessarily drawn more heavily on case studies from underground coal mining

than from surface mining and from non-coal mining. Nonetheless, the findings and conclusions

are applicable to all sectors of mining.

6

Dissertation Format

In the following chapters, a study of several cases of safety and health technology introductions

to the mining industry will be presented. These cases were used to identify and demonstrate the

factors that govern success for new safety and health technologies in mining, and guidelines for

the introduction of future safety and health technologies will be presented.

In Chapter 2, background for this study is presented, including an extensive review of the

relevant literature on the economics of technological change, the effect of policy on

technological change, the assessment of environmental control technologies, and the assessment

of technology readiness.

In Chapter 3, a detailed description of study methodology is presented, including an overview of

the methods of causal tree analysis and bowtie analysis.

In Chapter 4, several case studies for safety and health technologies are introduced. In this

chapter, no analysis or commentary on these cases is provided; rather, this chapter only presents

the relevant history of the research, development, diffusion, and regulation of each of the

technologies. The chapter is organized into two sections: Safety Technologies (which include

case studies for refuge alternatives, self-contained self-rescuers, communications and tracking

systems, proximity detection systems, and LED cap lamps) and Health Technologies (which

include case studies for noise controls for continuous mining machines and noise controls for

roof bolting machines). Each case study is discussed in a sub-section which concludes by

identifying indications that the technology introduction achieved either a successful or an

unsuccessful outcome.

7

In Chapter 5, causal tree analysis is used to identify the root causes for each of the successful and

unsuccessful outcomes identified in Chapter 4. The structure of this chapter mirrors Chapter 4

with the chapter being broken into two main sections – Safety Technologies and Health

Technologies – and each of these main sections being broken into subsections, each of which is

dedicated to one case study. Each subsection in Chapter 5 concludes by giving the root causes

for the success or failure of the technology introduction. The chapter concludes by combining the

results of all of the causal tree analyses to identify a generalized set of root causes for the success

or failure of new safety and health technology introductions.

In Chapter 6, the generalized root causes of successful and unsuccessful safety and health

technology introductions identified in Chapter 5 are used to conduct a bowtie analysis to develop

a set of strategies to prevent the promulgation of legislative or regulatory mandates for

technologies that are unlikely to achieve success as well as a set of strategies to mitigate the

negative consequences that would be experienced in the event that such a mandate is enacted.

In Chapter 7, a set of guidelines and recommendations for the introduction of new safety and

health technologies to the mining industry are presented. These guidelines and recommendations

are based on the results of the analysis in Chapters 5 and 6.

Finally, in Chapter 8, conclusions are presented.

8

Chapter 2: Background and Survey of Pertinent Literature

2.1 The Economics of Technological Change

To understand the processes through which new technologies are introduced to an industry it is

important to understand the economics of technological change. Extensive research has been

conducted to understand the economics that drive technological change and how regulatory

actions can influence those economics. Foundational work in this field was completed in the first

half of the twentieth century when researchers laid out economic theories of technological

change [2]. Schumpeter describes three stages in the process through which a new technology is

introduced: Invention, Innovation, and Diffusion. Invention refers to the development of a new

technology. Through innovation, this new technology is refined into a product that can be

commercialized. Finally, the product gradually becomes widely used through diffusion.

Research has been conducted to understand how firms make decisions during each of these

stages. A review and summary of some analytical frameworks for developing such an

understanding is given in [3]. Models for the invention and innovation stages of technological

change can be broadly categorized into two approaches, the first of which is to assume that

firms’ decisions regarding funding for research and development (R&D) are governed by an

effort to maximize value, and the second of which is to assume that firms base R&D funding

decisions not on economic optimization but on some other set of rules, for example a previously

established company policy or a set of “rules-of-thumb” [3, 4].

Under the assumption that firms act to maximize value, one can model the output of R&D as

“knowledge capital,” an asset that the firm can use to gain a competitive advantage [5, 6]. In this

way, R&D can be viewed as an investment activity; however, there are important peculiarities to

this type of investment that differ from investment in tangible assets. These differences include

9

the facts that the uncertainty associated with the outcome of R&D investments is very high, the

products of R&D are inherently intangible, and spillover of benefits to competing firms is

difficult or impossible to avoid [7]. The impact of uncertainty on R&D investment has been

investigated in terms of the implications for funding decisions [8, 9]. When coupled with the

inherent intangibility of R&D products, this high level of uncertainty makes it difficult,

especially for smaller firms, to secure funding, and may result in underinvestment. The other

major difficulty for R&D investment is the fact that spillover of benefits to competing firms is

difficult to avoid; in other words, it is difficult to prevent others from somehow making use of

the knowledge developed through R&D efforts [10, 5, 11, 7]. This issue of spillover may also

have the effect of reducing R&D investments.

If investment in R&D, and thereby in the invention and innovation of new technologies, is

viewed as being driven by decisions to maximize the benefits of the generated knowledge

capital, it is reasonable to conclude that invention and innovation can be induced by altering the

costs through policy and that this induced innovation can be understood from a profit-driven

perspective. However, some suggest that industries do not make R&D funding decisions based

on optimizing criteria. Rather, the high level of uncertainty and intangibility of R&D outcomes

necessitates that firms use a set of established routines or “rules of thumb” to make these funding

decisions [12]. If the assumption that R&D funding decisions are based on some economic

optimization is removed, then it becomes much more difficult to predict the impact of policy

designed to change the costs associated with safety, health or environmental impacts. Some have

argued that a new regulation that forces firms to re-evaluate their routine decision-making rules-

of-thumb, a “win-win” scenario can arise as the firm both complies with the new regulation and

10

also discovers a more efficient way of doing business [13, 14]. This “win-win” theory has been

met with skepticism and contrary findings have been published [15].

Following the invention and innovation of a new product, the gradual process of diffusion

begins. Theories to describe the diffusion process can be traced to two influential models. Both

models seek to explain the empirically observed S-shaped curve by which the number of

adopters grows. Initially only a few users adopt the technology at a slow rate. This is followed by

a period of rapid growth and then another slower period as the last few users adopt the

technology. This diffusion pattern has been consistently observed and documented for a wide

variety of technologies [16].

The first model to explain this pattern is referred to as the probit or rank model and attributes the

S-shaped diffusion curve to differences in the returns received or expected by various potential

users [17]. In this model, each user weighs the cost of the new product against the value it is

expected to provide. Since new products generally become less expensive as time passes, more

potential users will adopt the technology as the price falls below their individual threshold value.

If it is assumed that the value of the product to potential users follows a normal bell-shaped

distribution and that the price of the product falls in a smoothly decreasing fashion, this model

results in the expected S-shaped curve for diffusion.

An alternate model to explain the S-shaped curve of diffusion is the epidemic model, which ties

the diffusion of a product to the dissemination of information about that product [18, 19]. In this

model, which considers diffusion to be analogous to the spread of an infectious disease, posits

that, as people try the new product, they become a source of information about the product for

others in the population. Therefore, as more people adopt the technology, the rate at which

11

information about the product is disseminated increases, and diffusion follows suit. This process

is modeled by differential equations that result in the desired S-shaped curve.

2.2 The Effect of Policy on Technological Change

A large body of literature exists in the environmental arena dealing with the effect of various

regulatory strategies on the invention, innovation, and diffusion of new control technologies.

Some have argued, using industry surveys as evidence, that incentive-oriented policies are more

likely to result in technology change through lower compliance costs as compared to prescriptive

regulatory approaches [20, 4]. Case studies from the U.S. automotive industry have been used to

show that performance-based standards can result in significant induced innovation and diffusion

of new technologies [21]. Others have argued, with evidence based on analytical models, that

performance-based standards create a disincentive to the adoption of environmentally friendly

technologies [22].

Another question is whether technology-forcing regulations are effective. Again, a large body of

research exists from the field of environmental regulation. In general, this literature finds that

properly designed technology-forcing regulations can be effective at driving technological

change and diffusion [23, 21, 24, 25]. However, for these policies to be effective, it is necessary

that the government have superior knowledge of the technology, its potential impacts, and the

economics of its adoption [4, 26]. This knowledge can be used to strategically push for

technologies that are beyond the current capabilities of the industry. If the government is at a

knowledge deficit to the industry, it is possible that opponents to regulation can use their superior

knowledge to postpone or halt new regulations [27].

12

2.3 The Assessment of Environmental Control Technologies

In the regulation of greenhouse gases from stationary sources, standards such as best available

control technology (BACT), reasonably available control technology (RACT), and lowest

achievable emissions rate (LAER) are used. These standards were promulgated under the Clean

Air Act (42 U.S.C. § 7475). The U.S. Environmental Protection Agency (EPA), along with state

agencies, use these criteria to determine what air pollution control technology will be used to

control specific pollutants. Permits under these requirements are determined on a case-by-case

basis by state and local permitting agencies, and the EPA maintains a publicly available database

of the decisions [28]. In making the case-by-case decisions about what technologies satisfy the

BACT (or RACT, LAER) requirement, regulatory agencies are required by the Clean Air Act to

consider the achievable emission reduction along with cost and to demonstrate that the selected

technology is feasible.

The technologies proposed by a firm in air permit applications for a new stationary source of

pollution, such as a power plant, for which the BACT standard applies, are evaluated according

to a top down methodology [29]. This methodology requires applicants to first identify a list of

the available control technologies, often using the online clearinghouse maintained by the EPA.

This list of technologies is then reduced by eliminating technically infeasible options. The

remaining technologies are ranked according by control effectiveness, and each technology is

evaluated in order of this ranking. The evaluation considers energy impacts, environmental

impacts, and cost effectiveness. The technology that is ranked highest in terms of effectiveness

that cannot be eliminated based on this evaluation is selected. Guidance for complying with this

process are provided by the EPA in the New Source Review Workshop Manual [30]. Attempts at

improving the efficiency and ease of this approval process have been made [31, 32].

13

2.4 The Assessment of Technology Readiness

In order to evaluate the maturity of a technology for application in the mining industry, it is

necessary to have a clearly defined metric that is as objective as possible. Clearly, the desire for

such a metric is not unique to mining. In many industries and applications, engineers attempt to

evaluate whether a given technology is ready for deployment and use. A commonly used metric

is the Technology Readiness Levels (TRL). The TRL constitute a 9-level scale on which

technologies and components can be more objectively evaluated.

NASA developed the original Technology Readiness Levels in the 1980s as a means of

internally evaluating technologies to be used in space exploration [33, 34]. These TRL

definitions were subsequently modified and adopted by several other organizations including the

United States Air Force. A report published by the United States General Accountability Office

(GAO) in 1999 summarized the results of an investigation into the technology development and

deployment practices in the Department of Defense (DOD) [35]. This report was critical of the

DOD tendency to take on high levels of risk by promoting emerging technologies with low

levels of maturity. To better monitor and control this risk, the GAO recommended that the DOD

adopt the use of the TRL system developed by NASA. The DOD’s implementation of TRL is

detailed in the guidance provided in the DOD Technology Readiness Assessment Deskbook, first

published in 2003 and subsequently updated [36, 37].

Other alternative scales have also been developed by the Department of Energy (DOE) [38], and

the European Space Agency (ESA) [39]. More specialized implementations have also been

developed, for example to evaluate the readiness of software applications [40]. Note that this is

far from a complete list of the numerous implementations of the TRL concept. Many of these

14

implementations are largely the same with the most substantial differences in how they define

the environments in which the technologies are to be evaluated.

Aside from the TRL scales themselves, methods of calculating and implementing TRL include

the Technology Readiness Level Calculator (TRLC) developed by the United States Air Force

[41], the Technology Program Management Model (TPMM) developed by the United States

Army [42] and the Technology Readiness Assessments used by the DOD and the DOE [43, 37].

The Technology Readiness Assessments and the Technology Readiness Level Calculator are

similar in that they give a set of questions that are aimed at addressing different aspects of

technological readiness such as feasibility, reliability, maintainability, repeatability, robustness,

ruggedness, cost, and existence of a market. For some of the questions, very similar text appears

in both the DOD and the DOE guidance documents. However, many of the questions are also

highly industry-specific. Given this, it would be problematic to try to directly apply these

guidelines to mining safety and health technologies.

Regardless of how the TRL is calculated or exactly which scale is used, there are advantages and

limitations to using this method as an assessment tool. The key advantages are that it provides a

common language with which the technology status can be clearly communicated, it gives a

means of recognizing and managing risks associated with technology transition, and it gives a

largely objective measure that can be used to make decisions concerning funding and technology

adoption. A NASA study using mission data and pre-mission TRL assessments attempted to

quantify the benefits of using TRL in terms of program cost [44]. This study showed that, by

reducing uncertainty, the variability of program costs was reduced by 30%. Another study aimed

to quantify the economic value of TRAs in the DOD’s funding of technology development

15

projects and in technology acquisition decisions [45]. Although this study did conclude that a

positive economic impact is present, insufficient data was available to fully quantify this impact.

Other studies have looked at the limitations and challenges associated with TRL. Through

interviews with employees at organizations that use TRL, one study identified challenges and

potential pitfalls of the system [46]. These challenges were grouped into three categories: system

complexity, planning and review, and assessment validity. Another retrospective study of NASA

projects identified challenges with TRL assessment associated with difficulty in setting

appropriate cost and performance metrics that can be applied across a broad range of systems

and subsystems [47]. All of these challenges underscore the importance of clearly defined

guidance on how TRL-based tools can be used. Since no such guidance exists in the mining

industry, research is needed to understand the factors that are critical to the success of safety and

health technologies in the industry and to develop guidance specifically for mining.

16

Chapter 3: Methodology

3.1 Overall Research Approach

Several historical and contemporary examples of new safety and health technologies being

introduced to the mining industry have been assembled; this information comes from a variety of

sources including research literature, government records, and consultation with subject matter

experts. These detailed histories were examined to determine what factors or conditions existed

at various points in time and whether these factors positively or negatively impacted the

successful introduction of the technology.

Clearly, a definition for success is needed. For the purposes of this study, success of a safety or

health technology is understood in terms of performance, diffusion, and expected impact on

safety or health. For this study, success is defined by three characteristics:

1. For a safety and health technology to be considered successful, there must be evidence

that the technology, when used in the manner intended and when performing as expected,

will provide a material improvement to the safety or health of workers.

2. There must be evidence that the technology will meet some acceptable level of

performance. This performance level would need to be defined for the technology under

consideration; and defining characteristics of performance are likely to include accuracy,

reliability, robustness, maintainability, interoperability, among others. The performance

level should be selected such that it provides reasonable confidence that the technology

will perform as expected (i.e. that it will provide the intended safety or health benefit and

will not cause deleterious unintended safety or health implications) under a range of

operating conditions.

3. It must be possible to effectively diffuse the technology to a large subset of the industry.

17

Using this definition of success, the historical record of several technologies were examined

retrospectively to find evidence of whether the technology has achieved a successful or

unsuccessful outcome. Indications that the outcome was successful would include:

• There is documented evidence of an achieved safety or health benefit

• Documented successful trials were performed

• If not mandated, there was wide-spread voluntary adoption

• There is an indication of broad applicability throughout the industry

Indications of an unsuccessful outcome would include:

• There are documented failures of the technology

• The technology’s use introduces a new hazard

• There are low levels of adoption despite demonstrated ability to meet regulatory

standards

• Judicial intervention in rule-making or enforcement occurs

• Miners strongly resist the deployment and use of the technology

• After-rule time extensions occur

In each case, the characteristics of the technology and/or the conditions surrounding the

technology that caused or contributed to the successful or unsuccessful outcome was identified.

In determining which factors contribute to or limit success, causal tree analysis was used to

determine the root causes of the technology failure or success. Once the root causes for each of

the successes and failures were determined, they were categorized into a set of generalized root

causes. These generalized root causes were then be used, along with generalized outcomes, to

build a bow-tie analysis that provided a means of developing strategies to prevent the enactment

18

of mandates that are likely to be unsuccessful and to mitigate the negative outcomes of such

mandates if they are enacted. The development of these strategies draws on the research

literature such as previously developed models for technology development and diffusion as well

as on evaluation metrics used in other industries such as BACT and TRL.

3.2 Data Compilation and Consultation with Subject Matter Experts

For each of the technologies, a thorough review of the research literature was conducted. In

addition, government records, such as patents, MSHA product approvals, legislative records, and

regulatory records, was reviewed as they relate to the technology. Finally, subject matter experts

(SMEs)1 for each technology were consulted to ensure the accuracy and completeness of the

historical account. Based on these reviews, a summary of the history of each technology was

written.

For technologies considered successful according to the definitions provided in the previous

section, both mandated and voluntarily adopted technologies were included. However, for

unsuccessful outcomes, only mandated technologies were considered. This is for two reasons.

The first is that the research aims to capture challenges unique to mandated technologies. The

second is to avoid confounding errors due to survivorship bias. In other words, for the case of an

unsuccessful safety or health technology that was not mandated, little information is likely to

have been recorded. This would lead to an over-weighting of information on technologies for

1 For this research, subject matter experts were selected to be individuals who had both technical expertise in the

particular technology being considered as well as direct experience of the development, diffusion, and deployment

of that technology. The SMEs selected were employed by federal research and regulatory agencies, academic

institutions, and mining companies at the time the events of the case study occurred and were directly involved in

these events. The perspectives provided by these individuals was invaluable to understanding the details and nuance

of these case studies that are not fully captured in public documents and research literature.

19

which more information just happened to be recorded. By focusing strictly on mandated

technologies, the impact of this bias is minimized.

3.3 Identification of Factors that Influence the Success of New

Safety and Health Technologies

For each of the successful or unsuccessful safety and health outcomes examined, a causal tree

analysis was conducted to find the root causes for that outcome. In this method, the outcome is

placed at the top of a tree, such as the generic example shown in Figure 1. Direct causes for this

outcome are identified and form the second tier of the tree. For each direct cause, intermediate

causes are identified, which form the third tier of the tree. This process is continued by adding

further tiers until the root causes are found at the bottom of the tree.

Figure 1: Generic Causal Tree Analysis Framework

20

To generalize the findings on the causes of successful outcomes for safety and health

technologies in mining, a generalized set of outcomes and a generalized set of root causes for

those outcomes were defined. This was accomplished by identifying similarities between the

successful outcomes found in each of the root cause analyses. As with the successful outcomes,

generalized unsuccessful outcomes for mandated safety and health technologies and generalized

root causes for those outcomes were also identified.

3.4 Development of Strategies to Improve the Likelihood of Success

for New Safety and Health Technology Mandates

For the general case of the failure of a safety or health technology mandate, a bow-tie analysis

was performed. Bow-tie analysis is a method typically used to develop mitigation strategies for

hazards, such as those found in occupational safety and health. A generic framework for bow-tie

analysis is given in Figure 2. This method was adapted for the purposes of this research to

develop strategies to minimize the likelihood of unsuccessful outcomes for mandated safety and

health technologies in mining. This modified bow-tie analysis framework is given in Figure 3.

Figure 2: Generic bow-tie analysis framework

21

Figure 3: Bow-tie analysis framework as applied in the proposed research

At the center of the bow-tie is the hazardous event that occurred. In modified bow-tie analysis

framework, the hazardous event is considered to be the promulgation, either through legislation

or regulation, of a mandate for a safety or health technology that is not likely to be successful.

The threats that potentially contributed to the event are placed to the left. In the modified

framework, these threats are the generalized root causes for the failure of mining safety and

health technology mandates. On the right side of the bow-tie are the outcomes. In the modified

framework, these are the generalized failures of mining safety and health mandates. With this

framework in place, it is possible to identify potential control measures which are intended to

prevent the threats from leading to the hazardous event, as well as recovery measures which are

intended to prevent the outcomes from occurring if the hazardous event occurs. In the modified

framework, the control measures are strategies that are expected to reduce the likelihood that a

mandate will be promulgated before the technology is likely to be successful, and the recovery

22

measures are strategies that are expected to mitigate the repercussions in the event that such a

mandate is promulgated.

The control measures in the bow-tie analysis (i.e. the strategies to reduce the likelihood that a

mandate will be promulgated before the technology is likely to be successful) were developed

through a combination of three approaches:

1. Established technology evaluation frameworks, such as BACT and TRL, were

considered, and strategies from these frameworks were applied and adapted as

appropriate.

2. The generalized root causes for successful safety and health outcomes were contrasted

with those for unsuccessful outcomes. Strategies to transform the conditions encountered

in the latter into the conditions encountered in the former were developed.

3. Subject matter experts in mining safety and health were consulted to review strategies

developed by the above two methods and to suggest revisions.

As with the control measures, the recovery measures in the bow-tie analysis (i.e. the strategies to

mitigate the repercussions in the event that an unsuccessful safety or health technology mandate

is promulgated) were developed through a combination of three approaches:

1. Established technology evaluation frameworks, such as BACT and TRL, were

considered, and strategies from these frameworks will be applied and adapted as

appropriate.

2. The generalized successful safety and health outcomes were contrasted with the

generalized unsuccessful outcomes. Strategies to transform the conditions encountered in

the latter into the conditions encountered in the former were developed.

23

3. Subject matter experts in mining safety and health were consulted to review strategies

developed by the above two methods and to suggest revisions.

The results of the bowtie analysis constitute a set of guidelines to maximize the likelihood of

successful outcomes, and minimize the likelihood of unsuccessful outcomes, for new safety and

health technology mandates.

24

Chapter 4: Case Studies of Safety and Health Technology

Introduction to the Mining Industry

The seven representative cases of new technologies, which informed the analysis of this study,

are introduced in this chapter. The interventions presented here include both technologies that

were forced to be developed through government mandate as well as technologies that were

voluntarily adopted by the mining industry. First, the following five safety interventions will be

presented.

Case 1: Refuge alternatives

Case 2: Self-contained self-rescuers

Case 3: Primary communications and tracking systems

Case 4: Proximity detection systems

Case 5: LED cap lamps

Then the following two health interventions examined are presented.

Case 6: Noise controls for continuous mining machines

Case 7: Noise controls for roof bolting machines

For each of these technologies, a thorough review of the research literature and other records has

been conducted and is documented in this chapter. From this review, indications of success or

failure for each technology have been identified. In Chapter 5, the causes of these indications of

success or failure are presented.

25

4.1 Safety Interventions

4.1.1: Case 1: Refuge Alternatives for Use in Underground Coal Mines

A refuge alternative (RA), also referred to as refuge chamber, rescue chamber, refuge shelter,

and similar names, is an enclosed place within a mine where miners can go to take refuge and

await rescue in the event that they are not able to escape the mine following a disaster such as a

fire, an explosion, a major roof fall, or an inundation. Two well-known types of RA are portable

RAs and built-in-place (BIP) RAs. A portable RA is a manufactured unit which can be a rigid

steel structure, an inflatable tent deployed from a steel skid, or some hybrid of the two, and is

brought into the mine and can be moved as the mine advances. A BIP RA is a room in the mine

that is isolated by either one block stopping for an RA in a dead-end entry or by a block stopping

at each end for an RA installed in a crosscut. Figure 4, Figure 5, and Figure 6 show a metal-type

portable RA, a tent-type portable RA and the door to a BIP RA, respectively.

Figure 4: Metal-type portable refuge alternative

26

Figure 5: A tent-type portable refuge alternative deployed in the Experimental Mine at the NIOSH facility in

Pittsburgh

Figure 6: Door to a built-in-place refuge alternative constructed in the Experimental Mine at the NIOSH facility in

Pittsburgh

27

Background on Refuge Alternatives Prior to the Sago Mine Disaster

The concept of providing a safe space within the mine for miners to go in the event of a disaster

is not new. Publications by the US Bureau of Mines suggested the concept as early as 1912 [48,

49]. A 1941 Bureau of Mines report described the construction of a built-in-place chamber which

was 75ft long by 8ft high by 11ft wide and connected to the surface by two boreholes to provide

air, communications, water, and food [50].

Section 315 of the Federal Coal Mine Health and Safety Act of 1969 granted the federal

government the authority to require refuge alternatives in underground coal mines:

The Secretary or an authorized representative of the Secretary may prescribe in

any coal mine that rescue chambers, properly sealed and ventilated, be erected at

suitable locations in the mine to which persons may go in case of an emergency

for protection against hazards. Such chambers shall be properly equipped with

first aid materials, an adequate supply of air and self-contained breathing

equipment, an independent communication system to the surface, and proper

accommodations for the persons while awaiting rescue, and such other equipment

as the Secretary may require. A plan for the erection, maintenance, and revisions

of such chambers and the training of the miners in their proper use shall be

submitted by the operator to the Secretary for his approval.

However, this requirement was never enacted or enforced due to concerns about the feasibility of

the technology. Rather, the paradigm was that in the event that they were unable to escape a

mine disaster, miners should erect a barricade across a dead-end entry by hanging curtain or

stacking block in order to create an isolated space.

28

In the late 1970s and early 1980s, the Bureau of Mines funded a research contract with Foster-

Miller, Inc. to develop guidelines for the design, construction, stocking, and maintenance of

refuge alternatives. The contract resulted in guidelines in the following topic areas: breathable air

supply, infiltration of harmful gases, chamber pressurization, chamber construction, chamber

location, power and lighting, equipment and supplies, communications, psychological aspects,

and training [51, 52]. While the use of refuge alternatives was implemented for non-coal mines

following a mandate in the 1977 Mine Act, technical challenges prevented their use in coal

mines. Therefore, the common practice in coal remained barricading.

The Call for Refuge Alternatives in Response to the Sago Mine Disaster

On January 2, 2006, the Sago mine disaster underscored a need for refuge alternatives. The Sago

disaster was unique in that it was unambiguously clear that if an RA had been available, miners

would have had a substantially better chance of survival. The miners at Sago were unable to

escape the mine and hung a curtain across a dead-end entry; however, this was not sufficient to

prevent them from being exposed to toxic levels of carbon monoxide (CO), and 12 of the 13

trapped miners died from exposure to this harmful atmosphere [53, 54, 55].

The public response to the Sago disaster was intense. One factor that contributed to the strong

public reaction was the reporting of false statements during the rescue that 12 of the 13 miners

had been found alive, when in fact there was only one survivor [56, 57]. But media attention and

criticism following the disaster was not only about this unfortunate miscommunication. In the

days and months following the Sago disaster, media coverage scrutinized the mine

management’s safety record and the government’s role in mine safety and health enforcement.

For example, the New York Times published a pair of editorials on January 5-6, 2006 which

called into question the independence and objectivity of mining regulatory agencies, saying that

29

“workers' risks are balanced against company profits in an industry with pervasive political clout

and patronage inroads in government regulatory agencies.” The editorials stated that “the Bush

administration's cramming of important posts in the Department of the Interior with biased

operatives from the coal, oil and gas industry is not reassuring about general safety in the mines”

and asserted that the miners “might have survived if government had lived up to its

responsibilities” [58, 59]. In addition, several media outlets scrutinized the safety record at Sago

and the history of citations and orders issued against the mine by MSHA [60].

Several investigations of the Sago Mine disaster were launched in the days following the

disaster. MSHA announced its investigation on January 4, followed by West Virginia which

announced that an independent investigation would be headed by Davitt McAteer, former

assistant secretary for MSHA under the Clinton Administration [61].

On January 9, Senator Robert Byrd (Democrat from West Virginia), along with Senators Arlen

Specter (Republican from Pennsylvania) and Tom Harkin (Democrat from Iowa), announced that

the Labor-HHS Appropriations Subcommittee would hold hearings beginning January 19

(rescheduled to January 21) on the role of the federal government in the Sago disaster [62],

saying:

In Congress, there are tough questions to be asked of the federal Mine Safety and

Health Administration. Is enforcement of coal mining regulations tough enough?

Are the regulations on the books today current enough to handle the challenges

posed by 21st century coal mining? Are mine hazards being minimized? These

and other issues demand scrutiny, and the miners' families deserve the answers.

Leading up to these hearings, several members of Congress were quoted questioning whether the

government was fulfilling its responsibility to provide miners with a safe place to work [63].

30

Senator Byrd said, "I don't believe that the federal government is doing enough to protect coal

miners from future tragedies,” and Senator Jay Rockefeller said, “We need congressional

hearings not only so that we can determine what happened at Sago, but, more broadly, about the

state of mine safety across West Virginia and across the country. Coal is on the rise in our

country and safety must be too.” A letter from a bipartisan group of 12 senators requesting a

series of budget hearings on budget and staffing levels for MSHA said, "We look forward to

sending strong, bipartisan mine safety legislation to the president for his signature before the end

of the year. The miners who died at Sago deserve no less."

Given the miscommunication of the number of survivors reported to the media, the media

scrutiny of the mines safety record and the role of the government in enforcing safety standards,

and the attention from Congress, it is understandable that there was a strong public outcry for

stronger mine safety regulation. Since the nature of the accident was such that it was clear that

the miners would have had a significantly better chance of survival if a refuge alternative had

been available, this outcry was, in large part, for legislation or regulation requiring refuge

alternatives.

Legislative Actions Following Sago

Days before the Senate hearings on Sago began and in the midst of intense public and media

attention, another mine disaster occurred on January 19, 2006 when a belt fire at the Aracoma

Alma Mine killed two miners. In the following week on January 25, MSHA issued a Request for

Information (RFI) to gather public input on “Underground Mine Rescue Equipment and

Technology.” Another week later, on February 1, Senator Byrd introduced the Federal Mine

Safety and Health Act of 2006, which was not enacted but contained several elements eventually

incorporated into the MINER Act.

31

At the end of March, the comment period on MSHA’s RFI ended, having gathered information

from several companies and organizations who represented refuge chamber technology as

feasible with minimal development required.

Shortly thereafter on May 16, Senator Michael Enzi introduced the MINER Act. Four days later

on May 20, a disaster at the Darby Mine No. 1 killed 5 miners, and four days after Darby, the

MINER Act passed the Senate. The Act also moved very quickly through the House of

Representatives, passing on June 7. A week later, on June 15, 2006, President George W. Bush

signed the MINER Act into law.

The rapid pace with which these actions were completed was undoubtedly fueled by the political

and social pressure to respond to the disasters at Sago, Alma, and Darby. The rapid succession of

events also makes it clear that it would have been difficult, if not impossible, to properly evaluate

claims on feasibility and technology readiness submitted to the RFI and provided at hearings.

The MINER Act that NIOSH conduct “research, including field tests, concerning the utility,

practicality, survivability, and cost of various refuge alternatives in an underground coal mine

environment, including commercially-available portable refuge chambers,” and to provide a

report to Congress on the results of this research within 18 months. (Section 13)

Research on Refuge Alternatives Following the MINER Act

In accordance with the MINER Act mandate, the NIOSH Office of Mine Safety and Health

Research (OMSHR) began conducting research on refuge alternatives and provided a report to

MSHA in December of 2007 [64, 65, 66]. This research included testing on four portable refuge

alternatives. Shortcomings were identified with these RAs having to do with heat dissipation,

time to deploy, and ability to maintain CO2 concentration at the suggested level. NIOSH

32

considered these deficiencies to be “sufficiently serious in three of the chambers to require

correction before deployment.”

All of the RAs tested had been approved by West Virginia based on representations of the

manufacturers and certification by professional engineers. The fact that serious deficiencies in

these RAs led NIOSH to conclude that “computational models and other engineering analyses

alone cannot be relied upon for approval and certification of complex systems such as refuge

chambers. The results of the testing indicate the need for independent evaluations and testing

beyond the chamber manufacturers.” Yet, at this time, no guidance for such independent testing

and certification existed [64].

The NIOSH report to Congress concluded that although “some commercially available portable

chambers have operational deficiencies that will delay their deployment in mines” and although

“there are some remaining knowledge or technology gaps for the design and specification of

refuge alternatives” that “the benefits of refuge alternatives and the general specification of these

alternatives are sufficiently known to merit their commercialization and deployment in

underground coal mines.” However, this report also acknowledged the rapidly changing state of

the art for refuge alternatives by recommending that “any regulations on the specification,

location, and conditions of use for refuge alternatives should accommodate the rapidly changing

state of knowledge and technology.” [64]

In addition to intramural research, NIOSH also contracted with Foster-Miller, Inc. to conduct a

study that concluded in 2007 to develop guidelines for design, deployment, and use of RAs [67,

68]. This report demonstrated a potential benefit of RAs by estimating the potential number of

lives that may have been saved in past mine disasters had an RA been available. While this

report provided guidance for technical topics such as heat mitigation, atmosphere management,

33

and explosion survivability, it also highlighted the need for further research to fully understand

the safety implications of these design elements.

MSHA Regulation on Refuge Alternatives

On June 16, 2008 MSHA published a Notice of Proposed Rulemaking (NPRM) for a refuge

alternatives regulation. Public comments were sought and four public hearings were held on July

29, July 31, August 5, and August 7, 2008 in Salt Lake City, UT, Charleston, WV, Lexington,

KY, and Birmingham, AL, respectively [69]. After the comment period on this proposed rule

closed on August 18, MSHA acted very quickly to finalize the rule on December 31, 2008 [70].

As with the passage of the MINER Act, the promulgation of this regulation proceeded unusually

rapidly as compared to the timelines typically seen for other safety and health regulations,

indicating the political pressure under which decisions were being made.

After the promulgation of this rule, legal actions were taken due to industry objections to the

rule’s requirements. Most notably, on October 26, 2010, the D.C. Circuit Court of Appeals, in

response to objections that MSHA had not provided adequate justification for the requirements

of the rule, issued a decision requiring MSHA to re-open the record on the regulation in order to

provide interested parties to provide further input [71]. In August of 2013, based on this ruling,

MSHA re-opened the record [72] and issued an RFI [73] requesting “data, comments, and

information on issues and options relevant to miners’ escape and refuge that may present more

effective solutions than the existing rule during underground coal mine emergencies,” stating

that responses to the RFI would “assist MSHA in determining if changes to existing practices

and regulations would improve the overall strategy for survivability, escape, and training to

protect miners in an emergency.”

34

The comment period for this RFI was originally set to run through October 7, 2013; however,

due to lingering questions about the safety of RAs and in anticipation of results from ongoing

research, multiple extensions were issued extending the deadline for comment submission to

December 6, 2013 [74], then to June 2, 2014 [75], then to October 2, 2014 [76], and finally to

April 2, 2015 [77]. Among the questions that drove these extensions were the buildup of heat and

humidity within the RA, the ingress of CO and other contaminants when miners entered the RA,

the explosion survivability of RA doors, valves, and other components, and the emergence of

new technologies related to communications, breathable air delivery, heat mitigation, and other

factors. Following the RFI closing, the record was again reopened on September 18, 2015 to

schedule a public meeting on October 19, 2015 at the MSHA National Mine Health and Safety

Academy in Beaver WV to discuss these and other remaining questions [78], and in November

of 2015, the RFI was once again re-opened until January 15, 2016 to allow comments stemming

from this public meeting [79].

The legal challenges to the requirements of this regulation and the repeated re-opening and

extending of the rulemaking process are indications that the mandate for refuge alternatives had

limited success.

Refuge Alternatives Training

In addition to research on the engineering performance of RAs, NIOSH and others also

conducted extensive research to provide guidance on training for RAs. This is of particular

interest as it pertains to the voiced forceful reluctance of many miners to utilize an RA in the

event of an emergency.

35

Investigations by the Mine Safety Technology and Training Commission (MSTTC), the West

Virginia Mine Safety Technology Task Force (WVMSTTF), the Government Accountability

Office (GAO), and others to assess coal miners’ readiness to self-escape, which identified

multiple deficiencies in the availability and effectiveness of training [80, 81, 82, 83, 53]. A later

report in 2013 from the National Academy of Sciences (NAS) identified similar deficiencies

[84].

NIOSH has conducted research on the self-escape competencies (SEC) that are needed by miners

to successfully escape a mine disaster. A reasonably comprehensive list of these competencies

was published in [85] and includes items such as “Realistic expectations about using refuge

chambers,” “Where to find refuge chambers,” “How to use refuge chambers,” and “when to use

refuge chambers,” as well as similar competencies related to SCSRs. A study published by

NIOSH in 2015 provided guidance on ways to improve mine workers’ SEC, recommending that

rigorous assessments of SEC are needed, that better evaluation tools are need to aid these

assessments, and that debriefing practices following training need to be improved [86]. Both

NAS and NIOSH concluded that SECs for which miners may need better training include

competencies related to refuge alternatives and SCSRs [84, 86].

Recommendations for training regarding refuge alternatives, as well as training programs

published by NIOSH and MSHA, advise that refuge alternatives should be used as a last resort in

the event that self-escape is not possible due to all means of egress being blocked or injury or, if

the design and deployment of the refuge alternative permits it, as a way station to rest,

communicate with the surface, or switch over SCSRs during self-escape [87, 88, 89, 90, 91, 92].

NIOSH has also published similar guidance for RA manufacturers to use in the development of

their instructional materials [93].

36

The fact that training advises miners to use RAs as a last resort may help to explain the

commonly observed reluctance of miners to utilize this technology; however, the reasons that a

miner would or would not enter an RA undoubtedly vary from person to person. As one NIOSH

training program put it, “In the end, it boils down to where they place their most faith – in the

mine rescue team’s ability to come get them or in their ability to make it out on their own” [87].

Indications of Technology Success or Failure for Refuge Alternatives

Although refuge alternatives are now common within the underground coal mining industry,

there are indications that the regulatory mandate for their use has not achieved as much success

as it could have. These indications include judicial intervention in rulemaking and after-rule time

extensions. In addition, there is strong resistance to the deployment and use of the technology by

miners; however, it is possible that this is due at least in part to miners being trained to only use

RAs as a last resort or as a way station during escape.

An analysis of these indications of technology mandate failure is presented in Section 5.1.1.

37

4.1.2 Case 2: Self-Contained Self-Rescuers

Background on Self-Contained Self-Rescuers and Regulatory Requirements

Since June 21, 1981, coal mine operators have been required to make a self-contained self-

rescuer (SCSR) available to each person who enters an underground coal mine in the United

States (30 CFR 75.1714). After the Sago Mine disaster, an emergency temporary standard

increased the requirement to two hours of breathable air per miner, and the MINER Act of 2006

added the requirement for an additional two hours of breathable air to be kept in caches at a

distance of no further than an average miner could walk in 30 minutes from the deepest working

area of the mine along the escapeway to the surface.

SCSRs provide breathable air by recirculating exhaled air through a chemical bed that produces

oxygen (O2) and absorbs exhaled carbon dioxide (CO2). The CSE SR-100, shown in Figure 7,

was approved jointly by NIOSH and MSHA as a one-hour SCSR on February 23, 1989 based on

42 CFR Part 84 (approval number TC-13F-0239). The SR-100 provides about 100 liters of

usable oxygen and has a rated duration of 60 minutes. Potassium superoxide (KO2), a yellow

solid that turns grey as it is reacted, is used as the oxygen-producing chemical bed. It is a yellow

solid but turns a dark grey as it is reacted. In addition, Lithium hydroxide (LiOH), a white solid,

is also used to absorb carbon dioxide.

A starter oxygen cylinder is used to activate the SR-100 unit and start the reaction. This is done

by pulling an actuator tag attached to the cylinder. Miners are advised that, once donned, the

SCSR should not be removed for any reason until safety is reached or until the oxygen supply is

completely depleted. Daily visual inspections are required to detect damage to the unit, and more

rigorous inspections are required every 90 days.

38

Figure 7: CSE SR-100 Self-Contained Self-Rescuer

The Response to the Sago Mine Disaster with Regard to Self-Contained Self-Rescuers

In the previous section on refuge alternatives, the public and legislative response to the Sago,

Alma, and Darby mine disasters was described. Much of the discussion there also applies to

SCSRs. As with RAs, it was very clear that more effective SCSRs or better knowledge on the

part of miners on how to use SCSRs could have significantly improved the miners’ chances for

survival at Sago. The apparent deficiencies of the SCSRs at Sago were poignantly described in a

letter by the sole survivor of the miners trapped at Sago, Randal McCloy Jr., published in the

Charleston Gazette-Mail on April 26, 2006 [94]:

[T]he mine filled quickly with fumes and thick smoke and … breathing conditions

were nearly unbearable. The first thing we did was activate our rescuers, as we

had been trained. At least four of the rescuers did not function. I shared my

rescuer with Jerry Groves, while Junior Toler, Jesse Jones and Tom Anderson

39

sought help from others. There were not enough rescuers to go around. … The air

was so bad that we had to abandon our escape attempt and return to the coal rib,

where we hung a curtain to try to protect ourselves. … The air behind the curtain

grew worse, so I tried to lie as low as possible and take shallow breaths. While

methane does not have an odor like propane and is considered undetectable, I

could tell that it was gassy… There was just so much gas. We were worried and

afraid, but we began to accept our fate… As time went on, I became very dizzy

and lightheaded. Some drifted off into what appeared to be a deep sleep, and one

person sitting near me collapsed and fell off his bucket, not moving. It was clear

that there was nothing I could do to help him.

The report on the West Virginia investigation of Sago, published on December 11, 2006

confirmed that CO exposure was the cause of death and provided information on the SCSRs

recovered from the mine [54]. Seventeen (17) SCSRs used by the miners were recovered from

the mine, in addition to several SCSRs carried into the mine by the rescue teams. The

investigators, and NIOSH researchers who performed evaluations of the SCSRs, were unable to

estimate the oxygen production of the recovered units. Estimates of the remaining oxygen-

producing capacity of a deployed SCSR depend on an estimate of how much potassium

superoxide is remaining unreacted in the unit. This can be completed by a visual inspection,

which is a subjective estimate completed by comparing the approximate quantity of unreacted

material (which is yellow in color) to the approximate quantity of reacted material (which

appears pale yellow or white in color). An alternative test is to grind the entire recovered

chemical into a homogeneous batch, then add portions of that batch to a liquid catalyst which

releases the oxygen from the unreacted material. Neither test gives an accurate estimate of the

40

oxygen production of the unit because neither test takes into account decreased air flow that can

occur during use due to particles fusing or becoming coated. In addition, after use, the units

continued to be exposed to the atmosphere, which would cause slight continued depletion of the

chemical bed [54].

The West Virginia investigation also discussed interviews conducted with miners who survived

the Sago disaster. A total of 33 persons were underground after the explosion for a period of time

sufficient to be exposed to harmful gases. Of these, 15 donned SCSRs that operated adequately,

14 chose not to don their SCSRs, 4 SCSRs were reported as not functioning properly, and 1

miner was injured such that he could not have donned an SCSR [54]. In these interviews, several

miners indicated that they chose not to use their SCSRs while others said that they removed

SCSRs to talk or because breathing was difficult.

The MSHA investigation report from Sago, published on May 9, 2007 [55] provided similar and

further findings. SCSRs recovered from the mine were visually inspected. However, in most

cases, it was impossible to determine whether the units would have passed the normal daily

inspections before the disaster due to the fact that the units had been opened and the conditions

of seals, the moisture or temperature indicator, and security bands could not be assessed.

Interviews with miners and mine records indicated that several of the miners did not have

required training and that inspections either were not performed or were not documented [55].

Also of note in the MSHA investigation was that miners reported difficulties in using the SCSRs.

Miners indicated difficulty opening the units, including one miner who stated that he had to use

channel locks to open his unit. Miners indicated that they had to perform the manual start

procedure to activate their SCSR, but it was not clear whether this was due to failure of the

starter oxygen or some other cause [55].

41

While the public reaction to the disasters of 2006 was intense and called for stronger mining

safety and health rules, the changes in rules regarding SCSRs were fairly mild as compared to

the changes for RAs, communications systems and tracking systems, which were technology-

forcing mandates. The rules for SCSRs, on the other hand, were not changed in the form of a

technology forcing mandate. An emergency temporary standard increased the requirement to two

hours of breathable air per miner, and the MINER Act added the requirement for an additional

two hours of breathable air to be kept in caches.

Identification of Issues Related to Quality Control and Manufacture

On February 26, 2010 the NIOSH National Personal Protective Technology Laboratory (NPPTL)

published a public notice stating that NIOSH and MSHA had opened a joint investigation

concerning a problem that CSE had identified and reported to NIOSH with the SR-100 [95]. CSE

had discovered that one lot of SCSRs delivered less than expected oxygen. Analysis by NIOSH

revealed that up to 1% of the units in the lot may have oxygen starter problems, and it was

suspected that a total of 4071 units may have been affected. At this time, MSHA and NIOSH

advised mine workers that to immediately don another SCSR in the event that the breathing bag

in their SCSR did not inflate and to perform the manual start procedure in the event that a second

SCSR was unavailable. Mine operators were advised to make backup SCSRs available to all

underground workers.

On May 10 of the same year, a press release from CSE stated that CSE was investigating the

starter oxygen issue and that “until the root cause can be identified, we must assume that the

potential for start-up oxygen cylinders to fail may extend to any field deployed unit, and not just

the serial numbers that were previously identified.” [96]

42

A public notice from NPPTL on June 23 provided an explanation for why NIOSH’s Long Term

Field Evaluation (LTFE) Program had failed to identify the starter oxygen issue because starter

oxygen failures in the LTFE had been attributed to environmental factors rather than to

manufacturing defects [97]. However, the starter oxygen failures reported by CSE had been

observed during an in-process quality control check conducted during production. The NIOSH

notice stated that “while there is still information to suggest that environmental factors may

increase the likelihood of these failures, the new information from CSE placed the source of the

observed failures back to the point of manufacture.” On the same day, NPPTL also published a

notice that the failure was expected to extend beyond the initial suspect production lot and that

CSE had stopped production of the SR-100 pending identification of the failure mode and the

identification of a resolution [98].

On September 29, 2010 NPPTL announced that beginning in October 2010, NIOSH and MSHA

would begin collecting and testing a sample of 500 SR-100 SCSRs using a quality assurance

(QA) approach to quantify the prevalence of failed oxygen starter problems among field-

deployed units [99]. The sampling and testing protocol to be used for this test, which was

designed to provide an adequate sample size to enable statistically significant conclusions, was

published on the same day [100].

NPPTL planned to complete the collection and testing of the 500 SR-100 units by the end of

December 2010 [101]. However, by the end of the year, only 80 of the 500 units had been

collected and tested [102]. Among those 80 units, no failures were observed. Difficulty in

obtaining more units was attributed to reluctance of mine operators to voluntarily provide units

because replacement units were difficult to obtain. Therefore, NIOSH began offering

replacement units from other manufacturers to replace the SR-100 units collected for testing.

43

On February 15, 2011 NPPTL published that 109 of the 500 units collected and tested and that

one (1) failure had been observed among those units [103]. By May 17, 2011, NPPTL had

collected and tested 269 of the 500 units [104]. Of those 269 tests, four (4) failures had been

observed, which was sufficient to conclude that the failure rate could not be assured to be less

than 1%. On July 29, 2011 NPPTL announced that sample collection and testing of all 500 units

was completed and that five (5) failures had been observed [105]. Per the protocol published in

September 2010, this was used to calculate the Limiting Quality level as greater than 1.25% and

less than 2% using ANSI/ASQC Standard Q3-1988 [106]. This was judged by NIOSH to be an

unacceptable failure rate for long-term deployment [105]. Plans for an orderly phase-out of the

SR-100 began to be developed at this time. Detailed results of tests were published in April,

2012 [107].

Also in April of 2012, NPPTL announced the phase-out of the SR-100 [108]. OSHA required

units in use for non-mining applications to be removed from service no later than May 31, 2012

[109], while MSHA required units that were worn or carried by miners or stored on mantrips to

be replaced with any other approved one-hour SCSR by April 26, 2013 and all units to be

replaced by December 31, 2013 [110, 111].

Prior Failure to Prevent Quality Control Issues

Following the identification and quantification of the starter oxygen quality control issue with

the CSE SR-100, questions around why prior evaluations of the SCSR failed to predict this

problem.

44

NIOSH had conducted long-term evaluations of field-deployed SCSRs, including the CSE SR-

100 under the Long Term Field Evaluation (LTFE). As far back as 1990, this testing of the SR-

100 revealed performance issues [112], notably including the identification of manufacturing

defects with the oxygen starter bottles: “Several units did not have oxygen in the starter bottles

requiring cold starts. In one heat-treated unit to be treadmill tested, the human test subject chose

not to continue when the oxygen level fell below 16%. It was later determined that the burst disk

was defective and that the venting of the oxygen was not a result of the heat treatment.”

However, the significance of the manufacturing defects were minimized by stating that the issues

had been resolved: “Laboratory environmental testing of the SR-100 has uncovered a

manufacturing defect in the burst disk of the oxygen starter bottle and a design problem with the

desiccant bag. Both of these problems have been corrected by the manufacturer.” The

researchers concluded that the design and manufacture of the units was satisfactory and that, if

properly maintained and inspected, that they could be relied upon, stating, “The major problem is

predicted to be not with the apparatus, but with training the user to inspect properly the

apparatus.”

A later NIOSH study from 1992 specifically noted quality control problems [113]: “A number of

quality control problem were discovered in the long-term field evaluation. These problems were

reported to NIOSH, MSHA, and the breathing apparatus manufacturers. In each case, action has

been taken to solve the problems.” Despite specifically recognizing quality control problems, the

report concludes that the primary issue is with degradation of the units in the field rather than

with manufacture, stating that the “results of this study suggest that the large majority of SCSR’s

that pass their inspection criteria can be relied upon to provide a safe level of life support

capability for mine escape purposes.”

45

Nearly identical wording appears in reports from 1994 [114] (“The results of this study suggest

that the large majority of SCSR’s that pass their inspection criteria can be relied upon to provide

a safe level of life support capability for mine escape purposes.”), 1996 [115] (“The results of

this fifth-phase SCSR test study at PRC suggest that the large majority of SCSR's that pass their

inspection criteria can be relied upon to provide a safe level of life support capability to allow

miners to escape safely during a mine emergency. However, the mining environment appears to

have caused some performance degradation in the CSE SR-100.”), 2000 [116] (“The results of

this sixth-phase SCSR test study at PRL suggest that the large majority of SCSRs that pass their

inspection criteria can be relied upon to provide a safe level of life support capability to allow

miners to escape safely during a mine emergency. However, the mining environment seems to

have caused some performance degradation in the CSE SR-100 and the MSA Portal-Pack.”), and

2002 [117] (“The results of this study suggest that the large majority of SCSRs that pass their

inspection criteria can be relied upon to provide a safe level of life support capability for mine

escape purposes. However, the mining environment seems to have caused some performance

degradation in the CSE SR-100, Draeger OXY K-Plus, and Ocenco M-20.”).

In 2006, the eighth and ninth phase results of the LTFE were published [118]. This was

published after the Sago Mine disaster and after the passage of the MINER Act and included a

more direct description of the failures observed with the CSE SR-100:

The results of this study suggest that some performance degradation was

observed. The CSE SR-100s exhibit problems with CO2 levels exceeding 4%

(65% of all units tested, with 29% of these occurring before 60 minutes); stuck-

together breathing hoses (19%) which were prone to tear; starter-O2 failure

(16%); breathing hose punctures and tears (9%); breathing pressures exceeding

46

+200 mm H2O or -300 mm H2O (36%); and loose particles in the breathing hose

(31%). The loose particles caused coughing in all human-subject tests.

Similar results and wording was also included in the publication of the tenth phase results of the

LTFE in 2008 [119]:

The results of this study suggest that the large majority of SCSRs that pass their

inspection criteria can be relied upon to provide a safe level of life support for

mine escape purposes. However, the mining environment seems to have caused

some performance degradation in all the apparatus to some degree. The CSE SR-

100 is exhibiting problems of CO2 exceeding 4% (66%), stuck-together breathing

hoses (11%), starter-O2 failure (16%), breathing hose punctures and tears (4%),

breathing pressures exceeding +200 mm H2O or -300 mm H2O (31%), and loose

particulates in the breathing hose (23%). The loose particulates caused coughing

in human-subject tests.

Despite the repeated identification of performance and quality control issues with the SR-

100 over the course of nearly two decades, the quality control issues with the oxygen

starter bottles that was reported by CSE in 2010 and eventually led to the discontinuation

of the SR-100 were apparently not recognized. This appears to be due to the propagation

of the alternative explanation that performance issues with the units were solely due to

degradation of the units in the field. In addition, the importance of previous observations

of manufacturing defects were discounted by considering the issued solved by the

manufacturer. Finally, the LTFE testing did not utilize statistically driven experimental

design and sampled an insufficient number of units to identify the issues of the sort

identified in the 2010-2011 test of 500 SR-100 units.

47

Indications of Technology Success or Failure for Self-Contained Self-Rescuers

The unacceptably high level of quality control problems with the CSE SR-100 SCSR represents

a documented failure of the technology, which is an indication of a failure of the mandate for the

use of SCSRs. In this case, the failure appears to lie in the testing and certification of the

technology rather than in the mandate itself.

An analysis of this indications of technology mandate failure is presented in Section 5.1.2.

48

4.1.3 Case 3: Primary Communications and Tracking Systems

Primary Communications Technologies

There are four main types of communications systems used in underground coal mines [120,

121, 122]:

1. Leaky feeder

2. Wired node-based

3. Wireless node-based

4. Medium frequency (MF)

5. Through-the-earth (TTE)

Leaky feeder systems have a long history in mining and tunneling applications [123]. Leaky

feeder cable, as shown in Figure 8, is a coaxial-type cable designed to radiate a portion of the

signal through a holes in its shielding, acts as a distributed antenna as well as a transmission line.

In this way, two-way communication signals are allowed to enter and exit the cable and to

propagate along the cable as needed. Coverage of a leaky feeder system depends is limited to the

areas of the mine where the leaky feeder system is run; however, it is possible to extend coverage

using antennas branching off from the leaky feeder line [122].

49

Figure 8: Leaky feeder cable

Node-based systems, also referred to as wireless-mesh systems, are formed from a number of

network nodes distributed throughout the mine. These nodes communicate with each other either

wirelessly (wireless node-based system) or through wires (wired node-based system). Regardless

of whether the communication between nodes is wired or wireless, the communication from a

node to the handheld radios is wireless. This is shown conceptually in Figure 9.

50

Figure 9: Conceptual drawing of node-based communications

Leaky feeder and node-based communications systems are the sometimes referred to as

“primary” communications systems. This indicates that these systems are used on a day-to-day

basis as the primary means of communication within the mine. In contrast, “secondary”

communication systems, including medium frequency and through-the-earth systems, are not

intended for routine day-to-day communications. Rather, these secondary systems are intended

to provide an alternative means of communication in the event of an emergency. For this chapter,

only primary communications system will be discussed.

Tracking Technologies

Tracking systems that are either commercially available or under development for underground

coal mines today operate using the following technologies [124]:

• Active Radio Frequency Identification (RFID)

51

• Local area network (LAN)

• Personal area network (PAN)

• Passive RFID

• Inertial MicroElectro-mechanical systems (MEMS)

• Ultra-wideband (UWB)

• Near-field communication (NFC)

RFID tracking systems utilize RFID tags, most commonly battery-powered active tags, and

RFID readers which measure the strength of the signals received from each uniquely identified

tag. Received signal strength indicator (RSSI) methods are used to determine the position of the

reader relative to nearby tags. Alternatively, rather than using RSSI, a zone-based RFID system

can be implemented in which the system does not determine a precise location of the reader and

only reports the position of the nearest tag. Since leaky feeder communications systems do not

typically have the capability of providing tracking information, RFID systems are often used

with leaky feeder installations. Tag-based tracking is shown conceptually in Figure 10, and an

example of the tags used in mines is shown in Figure 11.

52

Figure 10: Tag-based tracking concept

Figure 11: Tracking tag used in underground coal mines

53

In contrast, a node-based communications system can be designed to also provide tracking

information. These systems can be configured as either local area networks (LAN) or personal

area networks (PAN) and either RSSI or time of flight (TOF) methods are used to determine

positions based on the signal strength received by the handheld radio, eliminating the need for

separate tracking hardware.

The two technologies described above represent the vast majority of installed tracking systems in

underground coal mines. However, other technologies have been trialed or are under

development, including passive RFID (in which passive RFID tags are used and a reader is

carried by the miner), inertial MEMS (which uses miniaturized inertial sensors – gyroscopes and

accelerometers – in a wearable device to continuously track and integrate the movement of the

miner), ultra-wide band, and near-field communication.

Public and Political Response to Mine Disasters of 2006

Following the Sago, Alma, and Darby mine disasters in 2006, the public response and political

response was to call for increased mine safety and health regulation. This was discussed in the

preceding sections as it relates to refuge alternatives and SCSRs, and much of the discussion for

these technologies also applies to communications and tracking systems. As with RAs and

SCSRs, it was clear, especially after the Sago disaster, that if the mine had a wireless

communications and tracking system, it likely would have greatly increased the miners’ chance

of rescue. In the months following Sago and as Alma and Darby occurred, the push from the

public and from lawmakers was that communications and tracking systems should be required,

with the rationale being that, if is possible in other industries, it should be possible in mining.

54

Following the Sago and Alma mine disasters, and before the passage of the MINER Act MSHA

issued an RFI requesting information on technologies that could improve mine escape and

rescue, which included technologies to track the location of miners before or after an accident

[125]. The views of several key stakeholders are well documented in congressional hearings as

well as in the responses to this RFI. The responses to this RFI can be found on MSHA’s website

[126].

In response to the RFI, NIOSH noted that additional research would be needed to provide

survivable communications systems [126]: “Research will be needed to harden this type of

equipment, develop reliable redundant transmission paths, and provide intrinsically safe backup

power solutions.” NIOSH also commented that “miner tracking is an additional communications

research need; existing systems do not pinpoint miner location or function if mine power is lost.

Research is needed to develop systems that rescuers can use to quickly locate miners, especially

those that are not able to communicate.”

Several coal operators commented that the technology is not mature enough to be put into use

without further research and development. For example, San Juan Coal Company stated [126]

that “improving the capability of knowing where miners are located during the shift would be

desirable. Some primitive systems are available now that would provide limited information

about when people passed a certain point and if they had passed another beacon somewhere else

in the mine. Their ability to pinpoint miner’s locations is extremely limited at this time.”

Similarly, CONSOL Energy said [126], “The coal mining industry has been presented recently

with a plethora of communications technologies purported to provide improved in-mine

communications and tracking capabilities. Many proposals are merely conceptual and most

others are unproven in this nation’s prevalent and diverse underground coal mining conditions.”

55

In contrast, communications and tracking equipment manufacturers and vendors purported to

have systems that were proven in the mine environment and that would provide highly reliable

communications and accurate tracking. For example, one vendor described their system as

having accuracy of a yard or better: “The miners wear tags that transmit a low frequency signal

which is detected by locator receivers. The receivers are spaced approximately a hundred yards

apart in the drifts of the mine. Using near field physics, the receivers can measure the distance to

the transmitter. These measurements provide a basis to determine the real-time location of a

miner to an accuracy of a yard or better as the miner travels down a draft.” Several other

companies, including Varis Mine Technology, Q-Track Corporation, InSet, Savi Technology,

Mine Site Technologies, and Siemens, also reported that their systems were ready for industry-

wide deployment [126].

Similar positions were expressed at the public hearings held by MSHA as well as hearings held

by the US Senate. In general, suppliers of communications and tracking systems characterized

their technologies as mature and ready for deployment, while research organizations and mine

operators felt that further research and development was needed for these technologies. As was

described in the sections for RAs and SCSRs, political pressures caused Congress to act rapidly

to respond to the disasters by mandating new technologies, making independent verification of

the technology’s readiness impossible.

MSHA Communications and Tracking System Evaluations in Response to Sago and Alma

Based on their preliminary investigation of Sago, MSHA had concluded that functioning

communication and tracking systems would have benefited search and rescue efforts and

therefore formed a committee to evaluate the technologies that could be adapted to underground

mines. In the months immediately following Sago and Alma, MSHA formed a committee to

56

evaluate the performance of commercially available communications and tracking technologies.

This committee published a report on June 13, 2006 describing results of tests that had been

conducted in the months immediately following the disasters in January of that year [127]. The

timing of this report is notable because it occurred after the MINER Act had already passed the

Senate on May 24 and the House of Representatives on June 7 but before the Act was signed into

law by the President on June 15.

In response to their RFI, MSHA had received information from vendors on numerous

communications and tracking systems. They selected six (6) of these systems to evaluate in

underground field tests. These systems included multiple different technologies such as wireless

mesh networks, ultra-wide band radio (UWB), and through-the-earth (TTE) communications.

Tests of these systems were conducted with the cooperation of CONSOL Energy at their

McElroy Mine in West Virginia. These tests had four objectives: (1) to evaluate how well signals

propagate in the underground environment, (2) to measure the overburden a TTE

communications system could penetrate, (3) to determine how interference affects system

performance, and (4) to quantify the accuracy of tracking systems [127].

The tests of the communications systems evaluations consisted of miners moving through the

mine along pre-planned routes away from a stationary base station transmitter and recording

where signals were lost. The routes through the mine included traveling through a track entry,

through a belt entry, through a dip, through an “S” turn, into a crosscut, and along a parallel

entry. In addition, tests were performed to evaluate the ability of the signals to penetrate a

stopping. The tests showed that, in general, the communications systems had ranges comparable

to their purported specifications along straight entries; however, signals were lost quickly when

the receiver was located in a non-line-of-sight (NLOS) location such as in a crosscut, past a dip,

57

or in a parallel entry. Given the limited timeframe for these tests (each system was only tested

over a period of one to two days, and all tests were completed over a period of approximately

two months), rigorous quantification of the performance was not possible [127].

Although the stated purpose of these tests included determining “the accuracy of tracking

systems,” the tests performed did not measure this accuracy in any quantifiable way. Rather, the

test consisted of a demonstration in which the system vendor set up the tracking system in a

straight entry of the mine and showed via a graphical interface that the position of a tracking tag

appeared to be in the correct position (i.e. the tag was shown to be midway between two

stationary nodes or close to a single node in an apparently accurate way). These tests were very

limited in that quantitative data were not taken and the tests were completely only once and only

along a single straight entry of the mine [127]. This represented the most rigorous independent

evaluation of the performance claims made by the tracking system vendors between the time of

the Sago and Alma disasters in January and the passage of the MINER Act in June of 2006.

Communications and Tracking Mandate in the MINER Act

The MINER Act requires mines to install wireless communications between the surface and

underground and to install tracking systems which can “provide for above ground personnel to

determine the current, or immediately pre-accident, location of all underground personnel.” The

“post-accident” communications system is required to be “redundant,” and the tracking system is

required to “be functional, reliable, and calculated to remain serviceable in a post-accident

setting.” Section 2, Part (1)(b)(ii) of the MINER Act reads:

Not later than 3 years after the date of enactment of the Mine Improvement and

New Emergency Response Act of 2006, a plan shall, to be approved, provide for

58

post accident communication between underground and surface personnel via a

wireless two-way medium, and provide for an electronic tracking system

permitting surface personnel to determine the location of any persons trapped

underground or set forth within the plan the reasons such provisions can not be

adopted. Where such plan sets forth the reasons such provisions can not be

adopted, the plan shall also set forth the operator's alternative means of

compliance. Such alternative shall approximate, as closely as possible, the degree

of functional utility and safety protection provided by the wireless two-way

medium and tracking system referred to in this subpart.

Specific performance metrics are not provided in the Act with regard to tracking accuracy,

communications system coverage, component hardening, backup power supplies, or other

considerations to ensure that the systems are functional after a disaster and that they will provide

sufficient levels of performance to materially affect the outcome of escape and rescue attempts.

Notably, the provision that mine operators can “set forth the operator's alternative means of

compliance” that “shall approximate, as closely as possible, the degree of functional utility and

safety protection provided by the wireless two-way medium and tracking system” will be of

significance in the interpretation and enforcement of this mandate.

It should be noted that the nature of this mandate, like that for RAs, is a technology-forcing

mandate. Although system vendors represented the technologies as mature, commercial products

were not approved and available to the mining industry that would provide wireless

communications and tracking of miners.

59

MSHA Enforcement of the MINER Act Mandate for Communications and Tracking

The compliance date for the communications and tracking mandate set by the MINER Act was

three years from the passage of the Act, or June 15, 2009. As that date approached, MSHA

issued a Program Policy Letter (PPL) on January 16, 2009 providing mine operators with

guidance on complying with the law [128]. Since the MINER Act had not provided specific

performance or design requirements for the communications and tracking systems and since

MSHA had not (and has not) enacted any regulation providing more specific requirements,

guidance was needed on the interpretation of the mandate. The PPL explained that “because fully

wireless communications technology is not sufficiently developed at this time, nor is it likely to

be technologically feasible by June 15, 2009, this guidance addresses acceptable alternatives to

fully wireless communication systems.”

The performance metrics provided in the PPL were also not presented as enforcement policy, but

rather as guidance: “This guidance represents MSHA’s current thinking with respect to two-way

communication and electronic tracking for use in mine emergencies. It does not create or confer

any rights for any person nor does it operate to bind mine operators or any other members of the

public.” Since no specific regulatory or legislative language exists to establish requirements for

system performance or design standards, the MINER Act mandate is accomplished through the

approval of the Emergency Response Plan (ERP) by the district offices through “the Agency’s

existing consultative process for approving mine plans, as opposed to the process for

enforcement decisions related to citations.” As allowed by the provisions of the MINER Act, the

PPL provides “the features MSHA believes would best approximate the functional utility and

safety protections of a fully wireless system,” but also allows operators the option to “propose

60

other approaches or systems, and the District Manager will exercise his discretion in evaluating

them.” [128]

The January 2009 PPL gives specific performance specifications for communications system

related to coverage area, permissibility, standby power, surface considerations, survivability,

maintenance, and other considerations; a summary of the key recommendations for

communications systems are provided in Table 1. The PPL also gives performance specifications

for tracking systems related to performance, permissibility, standby power, capacity, scanning

rate, surface considerations, survivability, and maintenance; a summary of the key

recommendations for tracking systems are provided in Table 2.

This guidance was reissued and revised in subsequent PPLs in 2011 [129] and again in 2014

[130]. Among the revisions in these subsequent PPLs was that it should be possible to monitor

the communications system from a remote site and that the system should determine the location

of miners in belt entries to within 4000 feet. These PPLs also provided more guidance on the

survivability of components by applying the requirement for redundancy to tracking systems and

by specifying how protection should be provided for components installed in vulnerable areas.

MSHA issued related PPLs in 2011 [131] and 2013 [132], respectively, to provide guidance on

the approval of communications and tracking devices for permissibility under 30 CFR Part 23

and to provide guidance on the prevention of electromagnetic interference with blasting circuits.

MSHA also issued a Program Instruction Letter (PIL) in 2011 to provide federal inspectors with

guidance on how to complete inspections of communications and tracking systems [133].

It is important to note that MSHA has not entered rule-making for communications and tracking

systems, but is instead relying on policy guidance in the fulfillment of the MINER Act mandate.

61

Table 1: Summary of key guidance provided by MSHA for communications system performance [128]

GUIDANCE

GENERAL

CONSIDERATIONS • Each group of miners traveling together should have an

untethered device for two-way communication with the surface

through voice and/or text

• Able to send an emergency message to each untethered device

• System should be installed to prevent interference with other

electrical systems, including blasting caps

COVERAGE AREA • Coverage throughout each working section of the mine

• Continuous coverage along escapeways

• Coverage within 200 feet of strategic areas such as belt drives,

transfer points, power centers, loading points, SCSR caches, and

other areas identified by the District Manager

• Communications must be provided at refuge alternatives

per 30 CFR §75.1600-3

PERMISSIBILITY • System must be approved by MSHA for permissibility

STANDBY POWER • Stationary components should have 24 hours of standby power

• Untethered devices should have 4 hours of operation beyond a

normal working shift (12 hours minimum total duration)

SURFACE

CONSIDERATIONS • Standby power to surface components should ensure continuous

operation

• A person trained in the operation of the system and

knowledgeable of the ERP must be always on duty

per 30 CFR §75.1600-1

SURVIVABILITY • A redundant signal path to the surface should be installed either

by installing two or more systems in two or more entries or by a

single system with two or more pathways to surface

• Major events or component failure in one signal path should not

disrupt system availability

• Components that are installed in vulnerable areas should be

protected

MAINTENANCE • Procedures should be established to provide communication

during system or component failure or maintenance

• Infrastructure should be inspected weekly

• Untethered devices should be inspected daily

• Manufacturer’s maintenance recommendations should be

followed

62

Table 2: Summary of key guidance provided by MSHA for tracking system performance [128]

GUIDANCE

PERFORMANCE • Determine location of miners…

o on a working section to within 200 feet

o in escapeways at intervals not exceeding 2000 feet

o within 200 feet of strategic areas such as belt drives, transfer

points, power centers, loading points, SCSR caches, and

other areas identified by the District Manager

• Determine direction of travel at key junctions in escapeways

• Determine the identity miners within 200 feet of refuge

alternatives

• System should be installed to prevent interference with other

electrical systems, including blasting caps

PERMISSIBILITY • System must be approved by MSHA for permissibility

STANDBY POWER • Stationary components should have 24 hours of standby power

• Individually worn or carried devices (i.e. tags) should have 4

hours of operation beyond a normal working shift (12 hours

minimum total duration)

CAPACITY • System should be capable of tracking the maximum number of

persons expected to be in the coverage area

SCANNING RATE • Update rate of no more than 60 seconds

SURFACE

CONSIDERATIONS • Standby power to surface components should ensure continuous

operation

• A person trained in the operation of the system and

knowledgeable of the ERP must be always on duty

per 30 CFR §75.1600-1

• System should display the last known position of miners when the

tracking device is not reporting

• Each miner should be uniquely identified

• Each reported position should be time-stamped

• Data should be stored for two weeks

SURVIVABILITY • Components that are installed in vulnerable areas should be

protected

• Data storage should not be impacted by communications

interruptions

MAINTENANCE • Procedures should be established to provide tracking during

system or component failure or maintenance

• Infrastructure should be inspected weekly

• Miner worn or carried should be inspected daily

• Manufacturer’s maintenance recommendations should be

followed

63

Research to Develop and Adapt Communications and Tracking Systems

The MINER Act directed the newly formed Office of Mine Safety and Health Research

(OMSHR) within NIOSH “to enhance the development of new mine safety technology and

technological applications and to expedite the commercial availability and implementation of

such technology in mining environments.” OMSHR fulfills this directive by conducting

intramural research and by funding extramural research through contracts. Between 2006 and

2016, OMSHR awarded more than 120 such contracts in 25 topic areas as a result of the MINER

Act [134]. Of these contracts, the topic area which has had the greatest number of contracts

awarded is “Emergency Communications and Tracking,” with 40 contracts awarded between

2006 and 2016. These contracts are listed in Table 3, and include contracts to develop novel

technologies such as inertial navigation and through-the-earth communications, as well as to

adapt more mature technologies from other industries or to improve technologies already

available in mining, such as node-based communications, leaky feeder, and RFID-based

tracking.

Several of these contracts have resulted in commercial products that are now widely used in the

mining industry. In particular, node-based and leaky feeder communications systems have been

widely adopted [121, 135], as have RFID tracking systems and tracking systems integrated into

node-based communications systems [120].

Extensive intramural research at OMSHR, closely tied to this extramural research, has also

enhanced the success of these technology development efforts. In particular, intramural research

on communications systems has enabled the development of guidelines for the design,

installation, and use of these systems [136, 137].

64

Table 3: NIOSH OMSHR extramural research contracts in the topic area “Emergency Communications and

Tracking” (2006 - 2016) [134]

Contract No. Title Contractor Start

Date

End Date

07FED717801 Subterranean Wireless Electronic

Communication System

U.S. Army CERDEC 10/1/2006 5/19/2009

08FED898353 Mine Communications Engineering and

Compatibility Guidelines

DISA Joint Spectrum

Center

5/22/2007 9/30/2009

200-2007-20388 Wireless Mesh Mine Communication

System

L-3 Global Security &

Engineering Solutions

(now Engility

Corporation)

5/25/2007 2/27/2009

200-2007-21249 Design and Demonstration of a Location

Tracking System for Underground Coal

Mines (Award 1)

Extreme Endeavors and

Consulting

7/25/2007 3/25/2008

200-2007-21250 Design and Demonstration of a Location

Tracking System for Underground Coal

Mines (Award 2)

L-3 Global Security &

Engineering Solutions

(now Engility

Corporation)

7/25/2007 11/30/2009

200-2007-22843 A Magnetic Communication System for

Use in Mine Environments

Lockheed Martin

Corporation

9/11/2007 7/31/2009

08FEB898345 Develop a Means to Model Network

Performance Using Network Simulation

Tools

U.S. Department of

Commerce, NIST

2/15/2008 8/15/2009

200-2008-24502 Passive Fiber Optic System for Locating,

Tracking, and Communicating with

Personnel in Coal Mines

US Sensor Systems Inc. 3/18/2008 2/28/2009

200-2008-24620C Development of a Wireless Test and

Measurement Tool for Use in Mines

Helium Networks 5/14/2008 5/14/2009

200-2008-25720 Through-The-Earth Wireless Real-Time

Two-Way Voice Communications

Alertek, LLC 8/1/2008 8/31/2010

200-2008-26293 Sprinkler Head Emergency

Communications

Commonwealth

Scientific and Industrial

Research Organisation

8/5/2008 8/5/2009

200-2008-26818 Ultra-Low Frequency Through-the-Earth

Communication Technology

E-Spectrum

Technologies

8/13/2008 11/30/2009

200-2008-26815 Leaky Feeder to Wireless Media Converter

Device Technology Development

Rajant Corporation 8/14/2008 7/30/2009

200-2008-24628 Supplementary Technologies for

Advanced Mine Communication Networks

Foundation

Telecommunications Inc.

8/19/2008 12/31/2009

200-2008-27444 Mobile Adaptable RF/IT Infrastructure -

Experimental (MATRIX)

St. Francis University

Center of Excellence for

Remote and Medically

Under-Served Areas

9/1/2008 8/14/2009

200-2008-26864 System Reliability and Environmental

Survivability

Foster-Miller, Inc. (now

QinetiQ North America)

9/1/2008 10/31/2009

200-2009-29066 Emergency Seismic Communication

System for the Mining Industry

Teledyne Brown

Engineering

3/23/2009 5/22/2010

200-2009-31292 Magneto-Inductive TTE Communications Ultra Electronics Canada

Defence, Inc.

8/25/2009 10/31/2010

200-2009-31502 Post-Accident AMS System CONSPEC Controls Inc. 9/1/2009 9/29/2013

200-2009-32117 Two-Way, Through-the-Earth Emergency

Communication System for Trapped

Miners and the Surface

Stolar Research, Inc. 9/4/2009 12/4/2010

200-2009-32021 Magnetic Communication System (MCS) Lockheed Martin

Corporation

9/10/2009 4/1/2011

200-2010-35295 Radio System Modifications for Improved

Mine Safety (Medium Frequency)

Kutta Technologies, Inc. 8/25/2010 8/25/2011

65

Contract No. Title Contractor Start

Date

End Date

200-2010-34687 Demonstration of Inertial Sensor Tracking

and Communication System

InSeT Systems, LLC 8/30/2010 3/2/2011

200-2010-35935 Feasibility Study: Vision-Aided Personal

Inertial Tracking System for Mining

Carnegie Mellon

University

9/8/2010 7/8/2011

200-2010-36005 Application of Extreme Power Line

Communication Methods to Mine

Environments

Northern Microdesign,

Inc.

9/13/2010 6/13/2012

200-2010-36317 Full-Wave Modeling of MF Propagation Pennsylvania State

University

9/30/2010 9/29/2013

200-2010-36140 Development of a Uniform Methodology

for Evaluating Coal Mine Tracking

Systems

Virginia Polytechnic

Institute

9/30/2010 1/4/2014

200-2011-39884 Through-the-Earth Communication

Systems for Underground Coal Mines:

Product Final Development and

Standardized Interface Definition

E-Spectrum

Technologies, Inc.

9/1/2011 11/30/2012

200-2011-39862 Wireless Through-The-Earth Modeling

and Support

Lockheed Martin

Corporation

9/9/2011 6/30/2012

11FED1113303 Low-Frequency Electromagnetic Noise

Cancelling Antenna System

Los Alamos National

Laboratory

9/30/2011 12/15/2015

200-2012-53624 Communication and Hazard Monitoring in

Bleeders and Remote Workings

Kutta Technologies 9/20/2012 9/30/2013

200-2012-53504 Medium Frequency Radio System

Modifications for Refuge Chamber

Situational Awareness


NA Resource Identification for Improvement

of Electromagnetic Compatibility (EMC)

in Underground Coal Mines

URS Corporation 3/25/2013 5/31/2013

200-2013-56128 Through-the-Earth (TTE)

Communications: Range Reliability

Improvements

Lockheed Martin 7/16/2013 4/15/2015

200-2013-56050 Kutta OutCall Micropower Messaging

System (KOMMS)


200-2013-56809 Advanced Software Radio Techniques for

Improved Range and Reliability of Digital

Through-the-Earth Communication

Systems

Vital Alert

Communications, Inc.

9/9/2013 7/17/2015

200-2014-58688 Through-the-Earth Communication

Antenna Feasibility Demonstration

Raytheon-UTD 9/1/2014 8/31/2015

200-2014-59253 Integration of Sensing Technologies for

Post-Event Monitoring of Hazardous

Conditions in the Mining Environment

SenSevere 9/1/2014 4/30/2016

200-2015-63501 Wireless Sensor Network with Methane

Gas Cloud Detector and Absolute Pressure

Sensor

Innovative Wireless

Technologies

9/1/2015 6/30/2016

66

The OMSHR intramural research program on communications and tracking focused primarily on

communications systems. In particular, the research on primary communications systems

(secondary communications systems will be discussed in Chapter 7) focused on measuring and

modeling the propagation of RF signals in underground environments [138, 139, 140, 141, 142,

143, 144]. Since this research provided an empirically verified basis for the design of

communications systems to ensure proper coverage in the mining environment, in which RF

signals behave much differently than they do in open air, it provided system designers with the

tools needed to ensure that their systems would perform as expected.

On the other hand, intramural research on tracking technologies at OMSHR was fairly limited

[124]. A rigorous evaluation of the accuracy of various tracking technologies in the mining

environment was not performed as the facilities to conduct such an evaluation were not

developed and the intramural research focus was on communications. While a number of

tracking technologies were commercialized for the underground mining market, the performance

of these technologies in terms of their ability to improve the success of escape and rescue efforts

has never been independently evaluated.

Research conducted by academic researchers and by international research organizations has

resulted in the development of several novel tracking technologies, which have been evaluated in

mining and non-mining environments [145, 146, 147, 148, 149, 150, 151], but these have not

provided a systematic comparison of the performance of commercially available systems.

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Indications of Technology Success or Failure for Primary Communications Systems

While there is wide-spread adoption of primary communications and tracking systems in

response to the MINER Act mandate, there is not documented evidence that these technologies

achieve a material improvement to safety or health. This is especially true for tracking systems,

where the requirements to locate miners to within 200 feet at working section and to within 2000

feet along escapeways has been the topic of considerable debate with regard to whether this level

of accuracy would provide mine rescue teams with sufficient information to effect successful

rescue. This indicates both success of the technology mandate, in that the technology is widely

adopted, but also failure of the technology mandate, in that there is not documented evidence of

an achieved safety or health benefit. The actual safety benefit of these technologies likely will

not be seen unless and until a mining disaster necessitates their use.

An analysis of this indications of technology mandate success and failure is presented in Section

5.1.3 for communications systems and in Section 5.1.4 for tracking systems.

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4.1.4 Case 4: Proximity Detection Systems for Continuous Mining Machines

Background on Proximity Detection Systems and Regulatory Requirements

Since the mid 1980’s when remote-controlled continuous mining machines were introduced to

the industry, there have been 43 fatalities in which a miner was pinned by a CMM. The Mine

Safety and Health Administration (MSHA) estimates that, in the majority of these fatalities, the

use of proximity detection technology may have been a preventative factor [152]. There are

currently five proximity detection systems that have been approved by MSHA for use in

underground coal mines [153]. It is important to note that this approval does not pertain to the

performance of the system, but is rather only an indication that the systems meet the

permissibility requirements in 30 CFR Part 18 meant to prevent mine fires and explosions.

All of the five MSHA-approved systems are based on similar technical concept; the system

includes a transmitting component that generates either a magnetic field or an RF signal, and the

strength of this signal is measured by another component of the system. One of these

components (either the transmitter or the receiver) is mounted on the mining machine, and the

other is worn by the miner. The measured signal strength is used to estimate the distance

between the miner and the machine or the position of the miner relative to the machine. Based on

this position, machine motion can be automatically inhibited. This type of technology was first

considered for use in underground mining in research conducted about 20 years ago [154].

Researchers at the National Institute for Occupational Safety and Health (NIOSH) developed the

first working prototypes of such a system for continuous mining machines and demonstrated the

feasibility of this technology through laboratory and field trials [155] [156]. NIOSH researchers

also published research on human factors related to these systems including the types of

warnings to be used and the interface between the miners and the system [157].

69

This original invention was patented by the government [158, 159]. From about 2004 onward,

these two patents were licensed to a number of manufacturers that further developed and refined

the initial invention. A number of other important patents were also filed that continued to

introduce new innovations. Despite the advances evidenced by the filing of these patents during

the time, from the year 2004 through 2009, there was little published research on proximity

detection.

In 2010, NIOSH resumed research focused directly on proximity detection. Prior research had

indicated that miners were inclined to stand in positions close to the mining machine in order to

see the visual cues necessary to stay safe and to efficiently mine [160, 161]. Based on this

research, NIOSH focused its efforts on the development of a next-generation proximity detection

system that would allow miners to stand close to the machine and remain safe. To accomplish

this, they developed a system that would determine the position of a miner and selectively

disable only the machine functions that would cause an injury [162] [163] [164]. While the main

focus of this research was on the development of this next-generation system, NIOSH research at

this time also quantified the effect of coal on proximity detection systems, and showed this effect

to be minimal [165]. In addition, NIOSH researchers conducted a series of interviews with

continuous mining machine operators to understand the effect this new technology would have

on the risk perception and risk behavior of miners [166] [167].

At this time research was also conducted to measure the performance of proximity detection

systems already in use in underground coal mines on continuous mining machines [168]. This

work was conducted primarily through a cooperative effort involving the West Virginia Mine

Safety Technology Task Force, mine operators, proximity detection vendors, and NIOSH. At the

time these field tests were conducted, a limited number of mines had installed proximity

70

detection systems. As such, the number of tests completed early on was small, and with small

sample sizes, it was not possible to generalize conclusions or to set performance standards.

MSHA has mandated the use of proximity detection systems for continuous mining machines

and has also proposed regulations to require the technology on mobile haulage equipment. Key

dates for these regulations are shown in Table 4. Leading up to and following the promulgation

of the continuous mining machine regulation in 2015, adoption of the technology has accelerated

dramatically. Per the regulation, the majority of continuous mining machines in the country are

now equipped with a proximity detection system.

Table 4: Key dates for proximity detection regulations

February 1, 2010 Request for Information (RFI) published

for continuous mining machine rule

February 1, 2010 Request for Information (RFI) published for

mobile machine rule

August 31, 2011 Notice of Proposed Rule Making (NPRM)

for continuous mining machine rule

January 15, 2015 Final Rule published for continuous mining

machines

September 2, 2015 Notice of Proposed Rule Making (NPRM)

for mobile machine rule

Identification of Electromagnetic Interference

In the months following the implementation of the regulatory mandate, some miners observed

adverse performance changes in the proximity detection system when used in conjunction with

another required piece of safety technology, the personal dust monitor (PDM). MSHA

determined that this problem was caused by electromagnetic interference (EMI) between the two

devices, and issued notice of the potential for this problem to mine operators [169]. Researchers

71

at NIOSH have confirmed that such EMI does occur and that it effectively renders the proximity

detection system temporarily inoperable [170].

Indications of Technology Success or Failure for Proximity Detection Systems

The failure to anticipate the potential for EMI between the PDM and proximity detection systems

represents a documented failure of the technology. This could be considered an indication of a

failure of the mandate for the use of proximity detection systems or an indication of a failure of

the mandate for the use of the PDM.

An analysis of this indications of technology mandate failure is presented in Section 5.1.5.

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4.1.5 Case 5: LED Cap Lamps

Historical Background on Mining Cap Lamps

Lighting has always been of critical importance in underground mining safety, and the

technology of mine illumination has continuously evolved. Given the long history of cap lamps –

a history that continues to influence the industry’s adoption new types of cap lamps and informs

the conclusions of this study with regard to safety technology adoption in the mining industry – it

is worthwhile taking a longer-term historical look at cap lamp technology.

As early as the 1st century AD, miners used candles for illumination underground. In the 16th

century, oil wick lamps were introduced and continued to be used up to as recently as 1920.

Carbide lamps were introduced in the 19th century along with the flame safety lamp. At the

beginning of the 19th century, the first electric light was invented (coincidentally, the first electric

light was invented by Humphry Davy, the inventor of the flame safety lamp). Throughout the

19th century, the technology of electric lights was improved, and in 1879, Thomas Edison

developed the first practical incandescent lightbulb. In 1915, incandescent lightbulbs were used

in the first electric cap lamp. Electric cap lamps were rapidly and widely adopted by the mining

industry, and incandescent cap lamps remained the dominant technology for cap lamps for

approximately a century [171].

The US Bureau of Mines (USBM) was formed in 1910, largely in response to several disastrous

mine fires and explosions. At this time, the concept of electric cap lamps appeared to be feasible,

but also by this time, flame safety lamps were a proven technology for controlling methane

ignition. Therefore, much of the early USBM research was focused on testing the potential for

electric cap lamps to ignite methane-air mixtures. In particular, testing was conducted to

determine what would happen if the bulb was broken, suddenly exposing the filaments to a

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methane-air atmosphere [172, 173]. This early research led to innovative means of preventing

ignition from electric cap lamps such as using spring-loaded contacts that would interrupt current

in the event the bulb shattered [174] as shown in Figure 12.

Figure 12: Miners' cap lamp assembly from the early 20th century with spring-loaded contacts designed to interupt

electric current in the event that the incandescent bulb shattered [174]

In 1914, two engineers from the USBM, John Ryan and George Deike (for whom the Deike

Building on Penn State’s University Park campus is named), formed the Mine Safety Appliances

Company (MSA) and sought out Thomas Edison to develop and commercialize electric cap

lamps. Edison, Ryan, and Deike designed a lamp with a small, rechargeable battery and a

miniature incandescent bulb with a tungsten filament [171]. The Edison electric cap lamp (Figure

13) was approved by the USBM in 1915, and by 1917, seven models of electric cap personal

mining lamps had been approved [175]. The technology was adopted rapidly; by August of 1916,

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approximately 70,000 lamps were in use and about 2,000 lamps per week were being purchased

according to USBM reports [175].

Figure 13: The Edison Electric Cap Lamp, approved by the Bureau of Mines for use in underground coal mines in

1915 [176]

In the first half of the 20th century, the USBM took an active role in developing electric cap lamp

technology as well as in promoting and tracking the adoption the technology [177, 178, 179], and

this undoubtedly was critical to the rapid adoption and success of the new technology. In

addition, the USBM set rules for the construction, installation, maintenance, and use of electrical

75

equipment, including cap lamps beginning in 1916 [180] and revised several times thereafter,

and in 1935, the USBM published guidelines specific to cap lamps focusing on proper

maintenance practices to not compromise permissibility or efficiency [181, 182]. These early

regulation and guidelines laid the groundwork for the regulation of cap lamp technology as it still

is today.

The Federal Coal Mine Safety Act of 1952 established requirements for permissibility, including

the requirement that only permissible electric lamps are permitted in gassy mines, and the

Federal Coal Mine Health and Safety Act of 1969 charged the Department of the Interior with

establishing “the standards under which all working places in a mine shall be illuminated,” and

the Federal Mine Safety and Health Amendments Act of 1977 extended these standards to non-

coal mines. Permissibility, inspection, and maintenance standards for cap lamps were based on

the requirements set forth by the USBM (Schedule 6D, 4 FR 4003, Sept. 21, 1939), but

requirements did not exist for the performance of cap lamps or other mine lighting. In 1970, in

fulfillment of the 1969 Coal Act mandate, the USBM proposed a regulation to require minimum

illumination in working places of at least 5 foot-candles and no more than 110 foot-candles. In

public hearings for this proposed regulation, mine operators and mining equipment

manufacturers objected to the performance requirements, saying that existing technology had not

been demonstrated to be capable of meeting the standard [176, 183].

In response to these objections, the newly formed Mine Enforcement and Safety Administration

(MESA), the precursor to MSHA, was charged with determining if the requirement for 5 foot-

candles was attainable. To accomplish this, a number of equipment operation tasks were

analyzed in terms of the visual cues that would need to be seen and the lighting that would be

needed to allow these visual cues to be seen. This analysis concluded that a minimum luminance

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of 0.06 foot-lamberts was needed [184]. Foot-lambert is a unit of luminance, whereas foot-candle

is a unit of illuminance. The two are related by the following equation:

𝐿𝑣 = 𝐸𝑣 × 𝑅

where 𝐿𝑣 is the luminance in foot-lamberts, 𝐸𝑣 is the illuminance in foot-candles, and 𝑅 is the

reflectivity, which is the fraction of the light that is reflected by the surface being illuminated.

Since the relationship between luminance and illuminance depends on the reflectivity of the

surface being illuminated, there is no direct comparison between this 0.06 foot-lambert

recommendation and the 5 foot-candle standard proposed by the USBM; however, for any

reasonable assumption about reflectivity, the 0.06 foot-lambert is much less stringent. In 1976,

regulations were promulgated with this less stringent 0.06 foot-lambert standard, with a

compliance date of 1978 [176].

At the time these regulations were being finalized and beginning to be enforced, the USBM and

MESA published a number of instructional guides and conducted a number of seminars on the

standards and on the proper design and implementation of cap lamps as well as machine-

mounted lighting, with 44 such one-day seminars being conducted over the three-year period

from 1976 to 1978 [185, 186, 187, 188, 189]. The active role of the government in educating the

industry about these standards and about the technology of mine illumination have shaped the

culture of the industry as it relates to this critical technology.

Driven by research on lighting technology and visual requirements for safety, the standards for

mine illumination have evolved over the half century since Congress first mandated illumination

standards with the 1969 Coal Act. But the standards have consistently been notably less stringent

than the lighting requirements for other industries, and the expectation for lighting has been less

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in underground mining than what is considered reasonable for safety in industrial environments

[176]. As such, the regulations around mine illumination have not represented a technology-

forcing mandate, and the primary driving force behind new illumination technologies has been

voluntary adoption.

Introduction and Diffusion of LED Cap Lamps

The first practical light-emitting diode (LED) was introduced in 1962 [190]; however, early

LEDs were limited to infrared light (which were used in electronics such as television remote

controls) or low-intensity colored light (which were used in electronics for indicators or seven-

segment digital displays). Key development in LED technology were the ability to produce white

light, the exponential increase in light output, and the simultaneous exponential decrease in cost.

By the mid-2000s, LEDs were capable of producing bright enough white light at a low enough

cost to be a feasible means of providing illumination [191].

When LED technology began to be widely adopted for illumination in the 2000s, cap lamp

manufacturers were quick to recognize the potential for this technology and began developing

LED cap lamps, which were first introduced to non-coal mines and were then submitted for

permissibility approval by MSHA, and MSHA approved the first LED cap lamp in 2008 [192].

A major advantage of LED cap lamps is that the lower power consumption allows for a much

smaller and lighter battery pack. As a result, cordless cap lamps are possible, in which the entire

cap lamp and battery can be contained within an all-in-one assembly that is worn on the miner’s

hard hat. This eliminates the need for the miner to carry a battery pack on their belt. The first

cordless LED cap lamp was approved by MSHA in 2010 [192].

78

LED cap lamps were shown to consume less energy to produce more light than incandescent

lamps [193]. In addition to the advantages of energy efficiency and light output, LED cap lamps

also offer advantages in terms of more accurate color rendering, decreased heat production, and

more consistent light output over as the battery is discharged and as the lamp ages. After an 8-

hour shift, the light output from an incandescent cap lamp powered by a lead-acid can decrease

by as much as 31% as compared to the start of the shift; in comparison, the light output of an

LED cap lamp powered by a nickel-hydride battery only decreases by 4% over the same period

[194]. LED cap lamps also offer advantages related to convenience and ergonomics: LED cap

lamps are lightweight, have a longer rated life, and generally have a faster charging time than

incandescent lamps [195].

All of these advantages have resulted in the rapid and pervasive adoption of LED cap lamps,

especially cordless LED cap lamps, and the majority of underground miners in the United States

now use such lamps.

Safety Benefits and Concerns of LED Cap Lamps

Although the factors that drove the adoption of LED cap lamps were largely around usability,

convenience, energy efficiency, and cost, the use of LED cap lamps has been shown to also have

safety benefits. NIOSH and others have done extensive research to demonstrate these safety

benefits.

Detection of tripping hazards was shown to be improved with LED cap lamps, enabling

detection times that were an average of 0.96 seconds faster compared to the incandescent lamps;

this improvement was attributed to the spectral content of the LED lamp making the hazards

more visible [196]. Other studies indicated that the detection time for slip and fall hazards could

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be improved by as much as 55% with LED cap lamps [197]. The use of LED cap lamps were

also shown to improve the ability of human subjects to detect hazards in their peripheral vision,

with improvements of up to 11% - 15% in detection time for the hazards [198].

Some negative results were also obtained in these studies on the potential safety improvements

of using LED cap lamps. The postural stability of human subjects was measured while they were

wearing LED and incandescent cap lamps. Postural stability can have a significant impact on the

occurrence of slip, trip, and fall accidents. No significant difference in postural stability was

detected for the two types of cap lamps [199].

The performance of cap lamps in a smoke-filled mine entry, such as would be encountered by

miners attempting self-escape following a disaster, was also tested. Specifically, the distance at

which human subjects could detect reflective tags hanging from the roof and mine rail on the

floor was measured for incandescent cap lamps as well as for LED cap lamps. The results

showed that the incandescent lamps allowed for a greater detection distance [200]. This can be

attributed to several factors including the possibility that more light was reflected off of the

smoke particles back toward the subjects for the brighter LED lamps.

A potential unintended consequence of introducing brighter lights into the underground

environment is glare. Glare can be bothersome and distracting, but it can also be hazardous as it

can leave a miner temporarily unable to see hazards in the area. Studies at NIOSH indicated that,

although the LED cap lamps are generally brighter than the incandescent lamps, they do not

produce significantly more discomfort glare [201].

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Indications of Technology Success or Failure for LED Cap Lamps

The rapid and wide-spread voluntary adoption of LED cap lamps is a strong indication of

success for this technology, and although the technology was not adopted solely for its safety

benefits, it does offer demonstrable safety benefits.

An analysis of the indications of technology success for LED cap lamps is presented in Section

5.1.6.

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4.2 Health Interventions

Health-related interventions in the mining industry have focused on controlling hazardous

exposures of noise, dust, and toxic substances, as well as musculoskeletal disorders (MSD). The

cases used for this study, focus on interventions to control exposure to noise and specifically, on

noise controls for two pieces of underground coal mining equipment: continuous mining

machines and roof bolting machines.

The problem of hearing loss in the mining industry is of significant concern; the industry once

had the highest rate of hazardous noise exposure [202] and one of the highest rates of hearing

loss, along with manufacturing and construction [203]. In addition to hearing loss, high noise

exposure can also lead to workers experiencing excess stress, tinnitus, sleep disorders, and

decreased work performance [204]. Moderate noise exposure can also be of concern because it

can interfere with hearing, potentially causing workers to miss audible warnings or audible

indications of a hazard, and it can lower a worker’s ability to maintain concentration on their job,

potentially making them more likely to become distracted or make mistakes [205].

In this section, an overview of noise control technology research, development, and diffusion

will first be provided. Following this, noise controls for continuous mining machines and roof

bolters will be discussed in particular.

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4.2.1 Noise Controls and Noise Exposure Regulations

Background on Noise Controls

The USBM had a long history of researching hearing loss prevention and noise controls for the

mining industry. The Federal Coal Mine Health and Safety Act of 1969 granted the authority to

set and enforce maximum noise exposure levels for coal mines, and the Federal Mine Safety and

Health Act of 1977 extended this authority to non-coal mines. In response to this mandate, the

USBM started conducting research on hearing loss prevention and noise controls. In 1971, a

USBM study found that 73% of underground coal miners were exposed to noise levels that

would be considered hazardous [206], and in 1976, NIOSH concluded that miners have a

measurably worse hearing than the average American [207]. The USBM conducted a series of

projects in the years following the 1969 Coal Act, which resulted in the characterization of noise

sources in the mining industry and in the development of noise control solutions [208]. These

mining machinery noise controls were published by the USBM in a handbook in 1983 [209], but

these solutions were never widely adopted by the mining industry [210].

Noise Control Research Following the Transfer of S&H Research from USBM to NIOSH

In 1996, the USBM was closed and its safety and health functions were transferred to NIOSH.

The hearing loss prevention research program remained in Pittsburgh under what is now the

Pittsburgh Mining Research Division (PMRD). At this time, NIOSH already had a hearing loss

prevention research program housed in the Division of Applied Research and Technology

(DART) in Cincinnati, Ohio. Also in 1996, DART published a “Preventing Occupational

Hearing Loss – A Practical Guide” [211], which set the strategic direction for future hearing loss

prevention research, including that to be conducted in Pittsburgh for mining. This strategy gave

primacy to engineering noise controls. Research was structured to prioritize the development of

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controls in order of effectiveness: (1) engineering controls to reduce noise at the source, (2)

administrative controls to reduce exposure through changes in procedures or behavior, and (3)

hearing protection devices such as ear plugs or muffs [211].

Another key action from DART at this time was the publication of a recommended noise

exposure standard [212], which included a Recommended Exposure Limit (REL) of an 8-hour

time-weighted-average (TWA) sound level of 85dBA, which remains NIOSH’s

recommendation. The 1998 recommendation from NIOSH updated a 1972 recommendation

from NIOSH [213]. Both the 1972 recommendation and the 1998 recommendations gave an

REL of 85dBA. However, the recommendations differed in how the TWA was to be calculated;

specifically, the 1972 criteria recommended an exchange rate of 5dB, whereas the 1998 criteria

recommended an exchange rate of 3dB. The exchange rate is the increase in decibels

corresponding to a halving of the allowable exposure time (or, equivalently, the decrease in

decibels corresponding to a doubling of the allowable exposure time). So, for example, with an

REL of 85dBA and an exchange rate of 5dB, exposure to 90dBA for four (4) hours would be

equivalent to eight (8) hours at the REL; however, with the same REL and an exchange rate of

3dB, exposure to only 88dBA for four (4) hours would be equivalent to eight (8) hours at the

REL.

The 1972 and 1998 NIOSH recommendations were based on risk assessments which evaluated

the excess risk of material hearing impairment as a function of noise level and exposure duration

for a 40-year working lifetime [212]. Excess risk is defined as the percentage of the population

exposed to occupational noise that would have material hearing impairment minus the

percentage of a population not exposed to occupational noise that would have material hearing

impairment. Material hearing impairment is defined as having an audiogram showing an average

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hearing threshold level (HTL) exceeding 25dB for both ears. The frequencies at which the

audiogram is to be conducted affects this definition, and a number of different standards have

been used for this frequency selection. In addition to the NIOSH risk assessments, other agencies

have conducted risk assessments for material hearing impairment. A comparison of the estimates

of excess risk for a 60-year-old worker with 40 years of working experience from NIOSH, ISO,

and EPA are shown in Table 5.

Table 5: Estimated excess risk of material hearing impairment at age 60 after a 40-year working lifetime exposure to

occupational noise for different definitions of material hearing impairment (From [212])

Material hearing impairment defined as an

average HTL for both ears exceeding 25dB at

500, 1000, and 2000 Hz

Material hearing impairment

defined as an average HTL

for both ears exceeding 25dB

at 1000, 2000, and 3000 Hz

Material hearing

impairment

defined as an

average HTL for

both ears

exceeding 25dB at

1000, 2000, 3000,

and 4000 Hz Average

exposure

level

(dBA)

1971

ISO

1972

NIOSH

1973

EPA

1990

ISO

1998

NIOSH

1972

NIOSH

1990

ISO

1998

NIOSH

1990

ISO

1998

NIOSH

90 21% 29% 22% 3% 23% 29% 14% 32% 17% 25%

85 10% 15% 12% 1% 10% 16% 4% 14% 6% 8%

80 0% 3% 5% 0% 4% 3% 0% 5% 1% 1%

This, and other information on the prevalence of noise-induced hearing loss in the mining

industry, would become the basis for a new regulation on noise exposure promulgated by MSHA

in 1999.

Introduction of New Regulatory Requirements for Noise Exposure

After the Federal Coal Mine Health and Safety Act of 1969, regulatory requirements for noise

exposure were established for coal mines, and after the Federal Mine Safety and Health Act of

1977, similar standards were established for metal/non-metal mines. The standards for both coal

and for non-coal set the permissible exposure limit (PEL) at 90dBA based on an 8-hour TWA

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with an exchange rate of 5dB. Both standards also required feasible engineering or

administrative controls to be implemented in order to reduce exposure below the PEL.

Beyond these similarities, there were significant differences between the requirements for coal

mines and the requirements for metal/non-metal mines. For coal mines, the attenuation provided

by hearing protection devices (ear plugs or ear muffs) were considered in the determination of

whether the PEL had been exceeded, but no credit for hearing protection was given in metal/non-

metal mines. In coal mines, when the PEL was exceeded, the operator was required to implement

a hearing conservation plan (HCP) for over-exposed miners, but the requirement for an HCP was

not in place for metal/non-metal mines.

The MSHA requirements prior to 1999 also significantly differed from the corresponding OSHA

standards which had been updated in 1983 (29 CFR 1910.95). The OSHA requirements also used

a 90dBA PEL with a 5dB exchange rate but also included an “action level” at 85dBA which

triggered the implementation of an HCP. These provisions for the HCP under OSHA had also

been updated to reflect recent advances in hearing conservation research.

In 1989, MSHA published an advance notice of proposed rulemaking (ANPRM) [214],

proposing to revise the standards for noise exposure. In this ANPRM, MSHA cited calls from

members of the mining community to reconcile the differences between the standards for coal

and metal/non-metal, to reconcile the differences between the MSHA and OSHA requirements,

and to consider the more conservative 85dBA PEL recommended by NIOSH in 1972. Public

comments were received in response to this ANPRM, and MSHA did extensive work to assess

the economic and technical feasibility of a change in the regulations.

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In December 1996, MSHA proceeded with the rulemaking process, publishing a notice of

proposed rulemaking (NPRM) [215]. The proposed rule would maintain the 90dBA PEL with an

exchange rate of 5dB, but would also implement an 85dBA action level similar to the OSHA

requirement. At the action level, mine operators would be required to enroll the miner in an HCP

and to provide the miner with hearing protection upon their request or in the event a significant

shift in hearing acuity was detected through the HCP. When the 90dBA PEL was exceeded, the

mine operator would be required to implement feasible engineering and administrative controls

to reduce exposure to the PEL. The feasibility of the controls would be determined by MSHA as

the feasibility for the particular mine in question to implement the control, and it would be up to

the mine operator to select whether engineering controls, administrative controls, or some

combination of the two would be used. To aid operators in the selection of controls, MSHA

would publish what it considered feasible controls in a Program Information Bulletin (PIB). In

the event that it was deemed infeasible for the mine to reduce the exposure to the PEL, the

proposed rule required that the operator must reduce the exposure to as close to the PEL as

feasible and to provide miners with hearing protection. The proposed rule also included a dual

hearing protection level of 105dBA, above which miners must wear both ear plugs and ear

muffs, and a ceiling level of 115dBA that could at no time be exceeded. Finally, the proposed

rule would no longer give credit for the attenuation provided by hearing protection when

determining whether the action level or PEL had been exceeded.

With the publication of the proposed rule in December 1996, MSHA sought written public

comment with a due date in February of 1997 [215]. After reviewing the written comments

received, MSHA decided to extend the comment period and to schedule a series of six public

hearings in Beckley, St. Louis, Denver, Las Vegas, Atlanta, and Washington DC [216, 217].

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Later that year, NIOSH published a report entitled “Prevalence of Hearing Loss for Noise-

Exposed Metal/Nonmetal Miners,” and MSHA re-opened the rulemaking record to allow public

comment on this report [218, 219]. The commenting period for this rule, including this and

subsequent extensions, closed in June of 1998, and in September of 1999, MSHA published the

final rule [220], which primarily amended 30 CFR Part 62. Minor changes were made in the final

rule as compared to the proposed rule, but the main provisions described above remained

unchanged. The decision to keep the PEL at 90dBA and the exchange rate at 5dB, as opposed to

NIOSH’s recommendation of 85dBA and an exchange rate of 3dB [212], was based on MSHA’s

conclusion that it would be infeasible for the mining industry to meet the NIOSH

recommendation [215, 220].

Expansion of the NIOSH Hearing Loss Prevention Research Program

Following the implementation of the 1999 MSHA noise rule, NIOSH significantly expanded its

mining hearing loss prevention research efforts in Pittsburgh. The research team increased from

about 3-5 researchers to about 16-24 researchers [210]. The facilities for this research were also

improved with the construction and accreditation of a reverberation chamber and hemi-anechoic

chamber large enough to accommodate underground mining equipment [221, 210]. In addition to

these large laboratory facilities, NIOSH constructed and obtained accreditation for a laboratory

for the testing of attenuation of hearing protectors and commissioned a mobile hearing loss

prevention unit, a 32-foot trailer containing a four-person booth for conducting hearing tests and

for evaluating hearing protectors [210].

Based on MSHA noise exposure data, NIOSH decided to focus its research first on continuous

mining machines and roof bolting machines. This research and the diffusion of noise controls for

those two pieces of equipment is discussed in the following sections.

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4.2.2 Case 6: Noise Controls for Continuous Mining Machines

Continuous Mining Machine Noise Control Research

Following the enactment of the new MSHA regulations on noise exposure, NIOSH began

conducting field measurements of noise exposure for workers around a variety of different

mining machines. It was found that 86% of continuous mining machine operators are exposed to

noise levels exceeding the PEL in the MSHA regulation [222]. Therefore, developing and

demonstrating the effectiveness of noise controls for continuous mining machines became a

priority for the NIOSH mining research program, with the goal of having feasible noise controls

published in an MSHA PIB [210].

Using the newly constructed and accredited hemi-anechoic chamber at the NIOSH Pittsburgh

facility and beam-forming microphone array technology, researchers identified the dominant

noise source from a continuous mining machine to be the conveying system [223]. Several

controls were developed and tested, the most successful of which was coated flight bars [224].

Testing both in the lab and in the field demonstrated that the coated flight bars reduced

operators’ noise exposure by 7dB [225].

Other notable engineering controls developed through NIOSH research for continuous mining

machines include a dual-sprocket conveyor chain, which was shown to provide a 3dB reduction

in exposure [226], a urethane jacketed tail roller, which was shown to provide a 2dB reduction

[227], and a vibration-isolated chain conveyor take-up [210]. Figure 14 shows a single-sprocket

conveyor on a continuous mining machine, which is was the standard configuration. Figure 15

shows a dual-sprocket conveyor, and Figure 16 shows a dual-sprocket conveyor with urethane-

coated flight bars.

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Figure 14: Single sprocket chain conveyor on a continuous mining machine (Source: [228])

Figure 15: Dual sprocket chain conveyor on a continuous mining machine (Source: [228])

Figure 16: Dual sprocket conveyor chain with polyurethane-coated flight bars on a continuous mining machine

(Source: [228])

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Diffusion of Continuous Mining Machine Noise Control Technologies

The effectiveness of noise controls developed for continuous mining machines by NIOSH was

demonstrated through both laboratory and field evaluations. The research program worked

closely with mining machinery manufacturers and material suppliers during the research process.

A major milestone was when Joy Mining Machinery, now owned by Komatsu, modified their

facilities to produce dual-sprocket chains and coated flight bars for their continuous mining

machines. The dual-sprocket chain technology provides benefits other than noise reduction; it

also reduces wear on the chain and sprockets and lengthens the life of the components [228,

226].

As a result of the demonstrated effectiveness of these noise controls and the fact that a major

manufacturer was supplying the noise controls on their equipment, MSHA determined that the

controls were “technically and administratively achievable” and listed them in a Program

Information Bulletin (PIB) [229]. Since the noise regulation requires operators to use any

feasible noise controls to reduce exposure below the PEL, this effectively requires the use of

these controls in cases where miners are overexposed. Dual-sprocket conveyor chains and

polyurethane-coated conveyor flight bars are among very few engineering noise controls listed in

the MSHA PIB, with the majority of the controls listed being administrative controls. The

controls listed by MSHA as “technically and administratively achievable” are shown in Table 6,

and the controls listed as offering promise are shown in Table 7.

It is difficult to assess how many continuous mining machines now have these controls installed,

but roughly a decade after they were developed, both the dual-sprocket conveyor chain and

coated conveyor flights are still offered as options on continuous mining machines [228]. The

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best way of assessing the effectiveness of these controls is to look at the reduction in miner noise

exposure, which is discussed in the following section.

Table 6: Engineering and administrative noise controls considered by MSHA to be technologically and

administratively achievable in reducing the noise exposure of miners operating or working around continuous

mining machines [229]

Engineering and administrative controls considered feasible for

continuous mining machines as published in MSHA PIB [229]

Remote control with proper positioning of the operator;

Treated cutting heads on auger miners (e.g., the application of stiffening gussets to the helix

and filling of voids with sand)

Proper maintenance, such as replacing bent or misaligned conveyor flights or sides and use of

a chain with proper tension or one having an automatic chain tension device

Polyurethane coated conveyor flights

Dual sprocket conveyor chain

Locate the shuttle car change-out point away from major noise sources (e.g., auxiliary fan)

Avoid idle parking in high noise areas

Keep miners away from auxiliary fans

Have mechanics and electricians avoid working near high-noise sources during maintenance

Reduce utility personnel working time near face and auxiliary fan

Limit operation of empty chain conveyors on all equipment (i.e., shuttle car, loading machine,

continuous miner, miner-bolter, and feeder-breaker)

Eliminate a high-pitched screech by instructing roof bolters to drill straight holes and to avoid

metal strap contact with the drill steel

Follow a cutting cycle (e.g., reduce cutting into roof and floor rock, cutting directly into in-

seam rock, and over sumping) to minimize noise generation from both the continuous mining

machine and the cutting process

Regulate engine RPM on diesel-powered shuttle cars during loading and dumping

Follow shuttle car loading and tramming procedures that minimize noise (e.g., time that the

conveyor chain is turning, increase distance from continuous miner and its boom, etc.)

Follow loading and tramming procedures for loading machines that minimize noise

Turn off any mobile equipment when not in operation

Maintain proper fan blade clearance on dust scrubbers associated with continuous-mining

machines

Constrained layer damping on the conveyor pan on an auger miner (e.g., the application of

visco-elastic materials covered with wear steel to isolate the chain and flights from the

conveyor pan line)

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Table 7: Engineering and administrative noise controls considered by MSHA to offer promise in reducing the noise

exposure of miners operating or working around continuous mining machines [24]

Engineering and administrative controls considered to offer promise for

continuous mining machines as published in MSHA PIB [229]

Transparent barrier between the operator and conveyor pan line

Constrained layer damping on the conveyor pan on a continuous ripper miner (e.g.,

the application of visco-elastic materials covered with wear steel to isolate the chain

and flights from the conveyor pan line)

Sand-filled conveyor decks

Enclosure and isolation of motors and pump housings where they have been demonstrated to

be a significant noise source

Vibration isolation mounts on motors/pumps where they have been demonstrated to be a

significant noise source

Isolated cutting bits (e.g., the application of vibration isolation materials between

the bits/block and the drum)

Sand-filled cutting heads

Rotate center bolter operator with center bolter helper, roof bolter operators with utility

personnel or shuttle car operators, miner-bolter operator with loading machine operator, or

continuous miner operator with shuttle car operator.

Noise controls for continuous mining machine scrubbers

Impact of Noise Controls on Continuous Mining Machine Operator Exposure

In 2007, researchers published an analysis of noise exposures before and after the enactment of

the 1999 noise regulation and concluded that noise exposure significantly declined after the new

regulation became effective [230]. Another analysis, published in 2017, went beyond this

analysis by considering a much larger data set and by examining exposure by mining sectors.

Overall, the mining industry saw an average 4.5dB decrease in exposure comparing

measurements before the rule change to measurements after the rule change. However, the

greatest reductions were seen at surface mines and at metal/non-metal mines. Whereas the

average reduction for all mines was 4.5dB, the average reduction was only 0.8dB for

underground coal mine [231].

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An analysis of MSHA citations related to the noise rule from 2000 through 2014 showed a

decreasing trend in violations since 2000 [232]. Since these violations are directly tied to

measurements of noise exposure and to the implementation of noise controls, it is reasonable to

interpret this decrease in violations as a decrease in hearing loss risk. The majority of the

violations were for insufficient corrective actions when noise exposure exceeded the 85dBA

action level or the 90dBA PEL, which represents an ongoing challenge despite the downward

trend in exposure, violations, and hearing loss risk.

To look specifically at the effectiveness of noise control efforts for continuous mining machines,

data from MSHA’s database of noise samples has been analyzed, which provides measurements

taken during mine inspection noise surveys [217]. The dataset provides noise dose measurements

as a percentage of the 90dBA PEL, so any dose over 100% would be considered an overexposure

by the regulation. The data was filtered to remove noise doses above 3200% of the PEL, which

corresponds to an average exposure for an 8-hour working shift of 115dBA, which is the ceiling

limit in the regulation. These outliers were judged to be anomalous sensor readings. The average

and standard deviation for the 90dBA PEL noise dose for continuous mining machine operators

was calculated on a year-by-year basis and is shown in Figure 17. In addition, the proportion of

the noise surveys for continuous mining machine operators for which the dose was over 100%

was also calculated on a year-by-year basis and is shown in Figure 18.

These figures clearly show that, since the enforcement of the 1999 noise regulation began in

2000, the average noise dose for these miners have steadily decreased and that the number of

miners who are overexposed has also steadily decreased. This represents a demonstrated

improvement in miner health risk exposure.

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Figure 17: Average noise dose for continuous mining machine operators as reported in the MSHA Noise Samples

data set [217]

Figure 18: Proportion of noise surveys for continuous mining machine operators for which the PEL dose was above

100% as reported in the MSHA Noise Samples data set [217]

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Indications of Technology Success or Failure for CMM Noise Controls

The demonstrated reduction in excessive noise exposure for continuous mining machine

operators since the enactment of new noise regulations in 1999 is a clear indication of the

success of this mandate, which drove the development and deployment of improved noise

control technologies.

An analysis of this indication of technology success is presented in Section 5.2.1.

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4.2.3 Case 7: Noise Controls for Roof Bolting Machines

Roof Bolting Machine Noise Control Research

NIOSH identified roof bolting machine operators as the second most over-exposed occupations

in underground coal mining, with 81% of operators having exposures that exceeded the MSHA

PEL [222]. Most of the noise exposure was found to occur during the drilling of the holes prior

to the insertion of the bolt [210]; therefore, the research focused on the drilling process. Noise

source identification using a beam-forming microphone array in NIOSH’s hemi-anechoic

chamber in Pittsburgh showed that the radiated noise during drilling primarily came from two

sources: the bit-roof interface and the drill-chuck interface [233].

Research for bolters therefore focused on the development and testing of noise controls to reduce

the noise from these sources. Controls were developed in collaboration between NIOSH and

companies including Corry Rubber Corporation and Kennametal, Inc. These controls included a

collapsible drill steel enclosure [234] and isolators for the drill bit and chuck [235]. In laboratory

testing, the use of the drill bit and chuck isolators together was shown to provide a 3-7dBA in

operator noise exposure [236, 237], the use of the collapsible drill steel enclosure was shown to

provide a 7dBA reduction [238], and the concurrent use of all three of these controls was shown

to provide a 13dBA reduction [239]. Field evaluations of the drill bit isolator showed a reduction

of 3-5dBA in operator exposure [240]. Conclusive field evaluations of the other controls were

not published.

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Diffusion of Roof Bolting Machine Noise Control Technologies

The effectiveness of noise controls developed for roof bolting machines by NIOSH was

demonstrated through both laboratory and field evaluations. The research program worked

closely with manufacturers and material suppliers, including Corry Rubber Corporation and

Kennametal, Inc., during the research process. This partnership resulted in drill bit isolators

becoming commercially available. On the other hand, chuck isolators and drill steel enclosures

were not commercialized.

As a result of the demonstrated effectiveness for the drill bit isolator, and the fact that a major

manufacturer was supplying the noise control, MSHA determined that the drill bit isolator was

“technically and administratively achievable” and listed it in a PIB [229]. Since the noise

regulation requires operators to use any feasible noise controls to reduce exposure below the

PEL, this effectively requires the use of this control in cases where miners are overexposed.

MSHA lists the chuck isolator and the collapsible drill steel enclosure as offering promise. The

controls listed by MSHA as “technically and administratively achievable” for roof bolting

machines are shown in Table 8, and the controls listed as offering promise are shown in Table 9.

It is difficult to assess how many roof bolting machines now have these controls installed. The

best way of assessing the effectiveness of these controls is to look at the reduction in miner noise

exposure, which is discussed in the following section.

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Table 8: Engineering and administrative noise controls considered by MSHA to be technologically and

administratively achievable in reducing the noise exposure of miners operating or working around roof bolters [229]

Engineering and administrative controls considered feasible for roof bolters as

published in MSHA PIB [229]

Wet drilling (where it can be implemented due to the roof bolter design and when compatible

with the geology and mining method)

Sharp drill bits

Starter drill steel to begin the hole

Straight drill steel (one piece and with thick wall, if conditions and dust collection allow)

Replacement of worn or defective drilling components (e.g., drill pot bushings or bearings,

worn steel, bent steel)

Maintenance of manufacturer-recommended drilling parameters for thrust, torque, and

rotational speed

Drill bit isolator

Table 9: Engineering and administrative noise controls considered by MSHA to offer promise in reducing the noise

exposure of miners operating or working around roof bolters [24]

Engineering and administrative controls considered to offer promise for roof bolters as

published in MSHA PIB [229]

Automated dust collection system or actuation of the dust collection system motors only

during drilling, or use of administrative controls to accomplish the same task

Exhaust conditioner (water box) and/or manufacturer-recommended exhaust muffler

Chuck isolator

Acoustic drill steel enclosure

Controls for optimizing the drilling parameters (drill feedback system)

Water misting system (i.e., injection of a small volume of water in a mist form into the drill

hole clearance system)

Grommet to isolate the drill steel and chuck

Acoustical liner in the tool tray

Damped drill steels

Impact of Noise Controls on Roof Bolter Operator Exposure

As was discussed in the preceding section for continuous mining machine noise controls, noise

exposures have been shown to have significantly declined since the enactment of the 1999 noise

regulation and [230], but whereas the average reduction for all mines was 4.5dB, the average

reduction was only 0.8dB for underground coal mine [231]. An analysis of MSHA citations also

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showed a decreasing trend in violations since 2000, indicating a reduction in hearing loss risk

[232].

And, as was done with the continuous mining machines, MSHA’s database of noise samples

[217] was used to assess noise dose changes for roof bolting machines since 2000. Again, the

data was filtered to remove noise doses above 3200% of the PEL, considering these outliers to be

anomalous sensor readings. The average and standard deviation for the 90dBA PEL noise dose

for roof bolting machine operators was calculated on a year-by-year basis and is shown in Figure

19. In addition, the proportion of the noise surveys for roof bolting machine operators for which

the dose was over 100% was also calculated on a year-by-year basis and is shown in Figure 20.

These figures clearly show that, since the enforcement of the 1999 noise regulation began in

2000, unlike the noise dose for continuous mining machine operators, which has steadily

declined, the average noise dose for roof bolting machine operators has remained relatively flat

as has the proportion of miners who are overexposed. This indicates that a demonstrable

improvement in miner health risk has not been achieved.

Indications of Technology Success or Failure for RBM Noise Controls

Unlike the case with continuous mining machines, the development of noise controls for roof

bolting machines has not resulted in a clearly demonstrable reduction in excessive noise

exposure for roof bolting machine operators since the enactment of new noise regulations in

1999. This is an indication that these controls have not achieved success.

An analysis of this indication of technology failure is presented in Section 5.2.2.

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Figure 19: Average noise dose for roof bolting machine operators as reported in the MSHA Noise Samples data set

[217]

Figure 20: Proportion of noise surveys for roof bolting machine operators for which the PEL dose was above 100%

as reported in the MSHA Noise Samples data set [217].

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Chapter 5: Causal Tree Analyses

In Chapter 4, the selected cases for several mining safety and health technologies for the mining

industry were described: including portable refuge alternatives, self-contained self-rescuers,

primary communications and tracking systems, proximity detection systems, LED cap lamps,

and noise controls for continuous mining machines and roof bolting machines. In particular, the

research, development, and diffusion of these technologies were studied to find indications that

the introduction of the technology had been successful or unsuccessful. As was discussed in

Chapter 3, indications of a successful outcome include:

• There is documented evidence of an achieved safety or health benefit

• Documented successful trials were performed

• If not mandated, there was wide-spread voluntary adoption

• There is an indication of broad applicability throughout the industry

Indications of an unsuccessful outcome would include:

• There are documented failures of the technology

• The technology’s use introduces a new hazard

• There are low levels of adoption despite demonstrated ability to meet regulatory

standards

• Judicial intervention in rule-making or enforcement occurs

• Miners strongly resist the deployment and use of the technology

• After-rule time extensions occur

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With these definitions in mind, indications of successful and unsuccessful outcomes were

identified for each of the technologies. The indications of successful outcomes that were found

are shown in Table 10, and the indications of unsuccessful outcomes that were found are shown

in Table 11. In this chapter, each of these is examined individually, and causal tree analysis is

applied to find the root causes of each successful or unsuccessful outcome. From these root

causes, commonalities are identified, and potential ways of improving the likelihood of

successful outcome are proposed.

Table 10: Indicators of a successful safety and health technology introduction

Primary communications and tracking systems are adopted throughout

the underground coal mining industry

LED cap lamps are rapidly and voluntarily adopted by mine operators

throughout the underground mining industry

Continuous mining machine noise controls achieve a demonstrated

reduction in noise exposure for operators

Table 11: Indicators of an unsuccessful safety and health technology introduction

Judicial intervention and after-rule time extensions occurred in refuge

alternatives rulemaking

Miners express strong resistance to using refuge alternatives

Unacceptably high rate of quality control failures occur for CSE SR-100

self-contained self-rescuers

No documented evidence exists showing that tracking systems achieve a

material improvement to safety

Electromagnetic interference (EMI) between continuous personal dust

monitors and proximity detection systems effectively render the

proximity detection system temporarily inoperable

Roof bolting machine noise controls fail to achieve a demonstrated

reduction in noise exposure for operators

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In the following sections, the causal tree analysis for each of the technologies examined are

presented along with a discussion of the results. First, the causal tree analyses for the safety

technologies are presented: refuge alternatives, SCSRs, communications and tracking, proximity

detection, and LED cap lamps. Following this, the causal tree analyses for the health

technologies are presented: noise controls for continuous mining machines, and noise controls

for roof bolting machines. Finally, this chapter will conclude by presenting a summary of the

commonalities between the results of these analyses and a discussion of what this indicates for

potential means of increasing the likelihood of success for new safety and health technology

mandates, which will feed into the next chapter in which recommendations are presented.

5.1 Causal Tree Analyses for Safety Interventions

5.1.1 Causal Tree Analysis for Case 1: Refuge Alternatives

In Section 4.1.1, a summary of the research, development, and diffusion of portable refuge

alternatives was presented. Although this technology has been a topic of interest for several

decades most of the development for the underground coal mining industry has occurred since

the occurrence of the Sago, Darby, and Alma mine disasters in 2006 and the subsequent passage

of the MINER Act of 2006, which mandated research into refuge alternatives, and the

promulgation of a 2008 MSHA regulation that mandated the use of refuge alternative. Two

indications that this safety technology mandate has been unsuccessful were identified:

1. Judicial intervention and after-rule time extensions occurred in refuge alternatives

rulemaking.

2. Miners express strong resistance to using refuge alternatives.

In this section, causal tree analyses of these two outcomes are presented.

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Causal Tree Analysis of “judicial intervention and after-rule time extensions occurred in

refuge alternatives rulemaking”

Figure 21 shows the causal tree for the outcome “judicial intervention and after-rule time

extensions occurred in refuge alternatives rulemaking.” Notes related to this analysis are shown

in Table 12. This outcome is evidenced by the filing of successful legal challenges to the

regulation [71] and the repeated re-opening and extension of the rulemaking process after the

passage of the final rule [73, 74, 75, 76, 77, 78, 79, 72].

The first step to performing the causal tree analysis is to identify the proximal cause for these

legal challenges and after-rule time extensions. It seems reasonable to conclude that the reason

these occurred was that after the enactment of regulations, lingering questions about the safety of

portable RAs remained in the minds of members of the mining community. These questions

lingered because, at the time of rulemaking, the risks associated with the use of RAs were not

well understood. Specifically, the risk of heat-related illness while in an RA, the risk of RA

components not surviving either primary or secondary explosions, and the risk of toxic gas

ingress into the RAs were not well understood. The fact that these risks were not well understood

is reflected in NIOSH research that has occurred since the passage of the regulation on the topics

of heat and humidity buildup inside RAs [241, 242, 243], cooling systems for RAs [244], the

explosion survivability of RA doors [245] and pressure relief valves [246], the ingress of harmful

gases into RAs during miner ingress [247], and the purging of harmful gases following miner

ingress [248]. The fact that concentrated, ongoing research in these topic areas has yet to provide

clear guidance for the design and use of RAs is clear evidence that these risks were not well

understood at the time the regulation was written. The above discussion is reflected in the top

three levels of the causal tree analysis in Figure 21.

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Figure 21: Causal tree analysis for “Judicial intervention and after-rule time extensions occurred in refuge

alternatives rulemaking” (See notes in Table 12)

Judicial intervention1 and after-rule time extensions2 occurred in refuge alternatives rulemaking

Questions about risks associated with refuge alternatives remain after rulemaking

Risks associated with the use of RAs were not well understood at the time of rulemaking:

- Risk of heat-related illness3

- Risk of components not surviving explosions4

- Risk of toxic gas ingress5

Rulemaking proceeded despite the identification of

need for further research on heat mitigation,

atmosphere management, and explosion

survivability6

Political and cultural pressures exist for immediate

action following 2006 mine diasters7

The timeframe

established by the

MINER Act allows for

limited research and

development8

Biases lead legislators to

judge that immediate

action is needed9

The MINER Act calls

for the use of RAs

despite a lack of

research indicating that

the technology is

mature10

Biases lead legislators to

fail to recognize

indications of

technological

immaturity

Rulemaking proceeded despite identification of

operational deficiencies in portable RAs11

Despite identifying

serious deficiencies with

available RAs, NIOSH

report to Congress stated

that the technology

merits

commercialization and

deployment12

Biases and political

pressures lead

researchers to understate

the seriousness of issues

identified through

research

Regulators fail to fully

recognize the

seriousness of identified

deficiencies

Biases lead regulators to

judge that immediate

action is needed and to

ignore indications of

technological

immaturity

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Table 12: Notes for causal tree analysis for “Judicial intervention and after-rule time extensions occurred in refuge

alternatives rulemaking” (See causal tree in Figure 21)

1 United Mine Workers v. MSHA, October 26, 2010 [71]

2 Multiple re-openings and extensions of public comment periods issued [73, 74, 75, 76, 77,

78, 79, 72]

3 Ongoing research on heat and humidity buildup [241, 242, 243] and cooling systems [244]

for refuge alternatives indicates significant knowledge gaps at the time the rule was enacted.

4 Ongoing research on survivability of RA doors [245] and pressure relief valves [246] for

refuge alternatives indicates significant knowledge gaps at the time the rule was enacted.

5 Ongoing research on contamination ingress [247] and harmful gas purging [248] for refuge

alternatives indicates significant knowledge gaps at the time the rule was enacted.

6 The Foster-Miller report commissioned by NIOSH in 2007 highlighted the need for further

research on heat mitigation, atmosphere management, and explosion survivability [67, 68].

7 See discussion on the call for refuge alternatives in response to the Sago mine disaster in

Section 4.1.1

8 The MINER Act required that NIOSH conduct “research, including field tests, concerning

the utility, practicality, survivability, and cost of various refuge alternatives in an

underground coal mine environment, including commercially-available portable refuge

chambers,” and to provide a report to Congress on the results of this research within 18

months. This timeframe set an expectation for rapid enactment of regulations.

9 Explain and cite relevant biases

10 A 1983 report developed by Foster-Miller through a USBM contract highlighted the

importance of considering the following in the development of refuge alternatives:

breathable air supplies, infiltration of harmful gases, chamber pressurization, chamber

construction, communications, psychological aspects, and training [51, 52]

11 NIOSH testing of refuge alternatives in 2007 identified shortcomings with RAs having to do

with heat dissipation, time to deploy, and ability to maintain CO2 concentration at the

suggested level. NIOSH considered these deficiencies to be “sufficiently serious in three of

the chambers to require correction before deployment.” [64]

12 The NIOSH report to Congress concluded that although “some commercially available

portable chambers have operational deficiencies that will delay their deployment in mines”

and although “there are some remaining knowledge or technology gaps for the design and

specification of refuge alternatives” that “the benefits of refuge alternatives and the general

specification of these alternatives are sufficiently known to merit their commercialization

and deployment in underground coal mines.” [64]

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Between the third and fourth levels of the causal tree analysis in Figure 21, the question that

must be answered is why the risks associated with the use of RAs was not well understood at the

time of rulemaking. Two causes were identified among those that contributed to this situation:

1. Rulemaking proceeded despite the identification of need for further research on heat

mitigation, atmosphere management, and explosion survivability

2. Rulemaking proceeded despite identification of operational deficiencies in portable RAs

It should be noted that a third cause could have also contributed. Manufacturers and vendors of

refuge alternatives technologies may have either intentionally or unintentionally misrepresented

the maturity level of their products. This cause was not explicitly included in this analysis

because it was judged that any recommendations designed to objectively detect the need for

further research or to appropriately act on identified deficiencies would necessarily also detect

misrepresentations of technology maturity.

The first identified cause (“Rulemaking proceeded despite the identification of need for further

research on heat mitigation, atmosphere management, and explosion survivability”) is evidenced

by the fact that following the passage of the MINER Act, and in partial fulfillment of Act’s

mandate that NIOSH lead research and development efforts on refuge alternatives, NIOSH

commissioned a contract with Foster-Miller to quantify the potential benefits of using RAs and

to identify areas in which further research and development is needed. The report from this

contract was published in 2007, after the passage of the MINER Act but before the finalization

of the RA regulation from MSHA. This report highlighted the need for further research on heat

mitigation, atmosphere management, and explosion survivability [67, 68].

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The second (“Rulemaking proceeded despite identification of operational deficiencies in

portable RAs”) refers to information reported by NIOSH to Congress in 2007 that testing of

refuge alternatives had identified shortcomings with RAs having to do with heat dissipation, time

to deploy, and ability to maintain CO2 concentration at the suggested level. NIOSH considered

these deficiencies to be “sufficiently serious in three of the chambers to require correction before

deployment” [64]. Asking why rulemaking proceeded despite these indications that further

research and development was needed and that the existing RA technologies exhibited

deficiencies is the next step in the causal tree analysis, which takes us to the fifth level of the

causal tree in Figure 21.

The most apparent reason that rulemaking proceeded despite the apparent need for research and

development is that political and cultural pressures were pushing for an immediate response to

the mine disasters of 2006. This was discussed in detail in Section 4.1.1: following the Sago

disaster and other disasters, media coverage, Congressional hearings, and political discourse

created an environment in which there were serious doubts about the nation’s ability to protect

miners’ safety and health and there was a call for immediate and decisive action to ensure that

disasters of this type did not occur again. The urgency of the political and cultural environment

under which the RA regulations were passed can be traced back to the passage of the MINER

Act, as shown on the left side of the sixth level of the causal tree in Figure 21, with the following

two causes:

1. The timeframe established by the MINER Act allowed for limited research and

development.

2. The MINER Act calls for the use of RAs despite a lack of research indicating that the

technology is mature.

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The first of these can be traced to the root cause that biases lead legislators to judge that

immediate action is needed. Specifically, cognitive biases such as the availability heuristic [249],

availability cascade [250], bandwagon effect [251], the law of the hammer [252], and the

identifiable victim effect [253] may have led legislators to conclude that immediate action was

needed to respond to the disasters. A brief discussion of each of these biases and the role the

played in the decision to rapidly enact the MINER Act is presented below.

The availability heuristic [249] is the tendency to overestimate the likelihood of events which

one remembers happening recently or which are more unusual or emotionally charged. In this

case, the disasters at Sago, Darby, and Alma were recent, unusual, and emotionally charged at

the time the MINER Act was being passed; it is likely that legislators, as well as others in society

overestimated the likelihood of similar disasters occurring in the future, which contributed to the

sense of urgency for legislation. Availability cascade [250] is the cycle by which propositions

which are emotionally charged are frequently repeated in public discourse, which, by the

availability heuristic, increases the emotional charge of these propositions. This self-reinforcing

cycle undoubtedly played a role in creating the mindset that immediate legislative and regulatory

action was needed. This appears to also have been reinforced by the bandwagon effect [251],

which is the tendency to hold beliefs that many other people also hold. The law of the hammer

[252] is the tendency to over-rely on familiar tools and methods, as captured by the idiom “If all

you have is a hammer, everything looks like a nail.” This cognitive bias surely played a role in

legislators judging that legislation was the best means of addressing the apparent need for

improvements to mine safety and health. Finally, the identifiable victim effect [253] is the

tendency to respond more strongly to risk when the potential victim of an event is personally

identified rather than a group of unidentified people. The personal stories of the victims of the

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Sago, Darby, and Alma disasters were covered extensively in the media in the months following

the disasters, notably including the poignant letters left by the victims at Sago. This

personalization of mining disaster victims was likely a factor in the thinking of legislators and

others.

The other root cause on the left side at the bottom of Figure 21 is that biases led legislators to fail

to recognize indications of technological immaturity. In particular, confirmation bias appears to

have played a role in leading legislators to the conclusion that refuge alternative technologies

either were already mature or could easily be developed to maturity. Confirmation bias [254] is

the tendency to seek out and remember information that confirms one’s beliefs or preconceptions

while ignoring information that disconfirms one’s beliefs or preconceptions. As was discussed in

Section 4.1.1, the discourse around mine safety in the media and from members of Congress

following the disasters of 2006 was largely motivated by the notion that the mining industry was

not making use of modern technologies to protect miners. This notion that available technologies

simply weren’t being used surely led legislators to think that new safety and health technology

mandates would be relatively easy to meet. Confirmation bias would have caused legislators to

more heavily weight evidence that reinforced this notion (e.g., testimony from vendors claiming

that they could provide effective solutions) and to discount evidence that contradicted this notion

(e.g., testimony stating that further research and development is needed).

Returning now to examine the right side of Figure 21 from the intermediate cause “Rulemaking

proceeded despite identification of operational deficiencies in portable RAs,” the question is why

the identification of deficiencies did not cause rulemaking to stall following the passage of the

MINER Act. Two causes for this have been identified:

111

1. Despite identifying serious deficiencies with available RAs, NIOSH report to Congress

stated that the technology merits commercialization and deployment.

2. Regulators fail to fully recognize the seriousness of identified deficiencies.

The first refers to the fact that the 2007 NIOSH report to Congress on their preliminary research

on RAs concluded that although “some commercially available portable chambers have

operational deficiencies that will delay their deployment in mines” and although “there are some

remaining knowledge or technology gaps for the design and specification of refuge alternatives”

that “the benefits of refuge alternatives and the general specification of these alternatives are

sufficiently known to merit their commercialization and deployment in underground coal mines”

[64]. In this way, although researchers had identified serious deficiencies, the implications of

these deficiencies were understated. Similarly, despite having seen these documented

deficiencies, regulators apparently failed to fully appreciate the seriousness of these deficiencies.

These are traced back to the root causes shown at the bottom right of Figure 21: “Biases and

political pressures lead researchers to understate the seriousness of issues identified through

research,” and “Biases lead regulators to judge that immediate action is needed and to ignore

indications of technological immaturity.” Both of these can be explained by similar cognitive

biases in the thinking of the researchers and the regulators, namely: confirmation bias [254],

availability heuristic [249], availability cascade [250], the identifiable victim effect [253], the

law of the hammer [252], optimism bias [255, 256], and the ostrich effect [256].

The availability heuristic, availability cascade, and the identifiable victim effect, played a role

similar to what was discussed for legislators above; the frequently repeated, emotionally charged

discussion of the recent events of Sago and other disasters created a greater sense of urgency.

112

This likely led regulators to feel that immediate action was needed and led researchers to feel

that a positive interpretation of the research was needed in order to accommodate this immediate

action. As with the legislators, the law of the hammer may also have led regulators to their most

familiar tool: regulation. Regulators and researchers appear to also have suffered confirmation

bias that caused them to discount evidence that contradicted the proposition that RA technology

was mature and effective. Finally, optimism bias and the ostrich effect may have led both

regulators and researchers to discount the evidence that there were deficiencies with RAs.

Optimism bias [255, 256] is the tendency to be overly optimistic when considering a decision

involving risk. In other words, although the risk that RAs might not be as safe as expected was

apparent in the identified deficiencies of the chambers, optimism bias caused regulators and

researchers to conclude that these deficiencies could be corrected. Similarly, the ostrich effect

[256] is the tendency to ignore an obvious risk (i.e., to stick one’s head in the proverbial sand). It

is possible that, although researchers and regulators recognized the import of the identified

deficiencies, they ignored this in decision making due to the ostrich effect.

In addition, these biases can be compounded by political pressures and interactions within or

between agencies whereby positions that do not align with the agendas of an agency can be

stifled either overtly through the silencing of those positions or more subtly through the

intentional or unintentional fostering of a culture in which those positions are not expressed.

The discussion above traces the causes for judicial and after-rule time extensions in the refuge

alternatives rulemaking process to four root causes which can all be attributed to cognitive biases

on the part of legislators, regulators, and researchers who were responsible for making key

decisions leading to the enactment of the regulation. These root causes are shown in Table 13.

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Table 13: Identified root causes for “Judicial intervention and after-rule time extensions occurred in refuge

alternatives rulemaking”

Biases lead legislators to judge that immediate action is needed

Biases lead legislators to fail to recognize indications of technological

immaturity

Biases and political pressures lead researchers to understate the

seriousness of issues identified through research

Biases lead regulators to judge that immediate action is needed and to

ignore indications of technological immaturity

Causal Tree Analysis of “Miners express strong resistance to using refuge alternatives”

In Section 4.1.1, the other indication of an unsuccessful outcome for the mandate for refuge

alternatives was that miners express strong resistance to the use of the chambers. It is common to

hear from miners that they will not ever use an RA, or at least that they won’t use them except as

a last resort. While these statements may not reflect what miners will actually do in a disaster, it

is a significant concern that miners may not use an RA in a situation where one could save their

life. The causal tree analysis for this is shown in Figure 22. Note that a significant portion of this

tree is shown in dashed lines. This is because at two parts of the tree, one of the intermediate

causes is that “risks associated with the use of RAs were not well understood at the time of

rulemaking,” which was also an intermediate cause in the causal tree shown in Figure 21.

Therefore, only the root causes are shown with dashed lines.

There are two apparent reasons why miners would be strongly opposed to using RAs; these

represent the second level of the causal tree analysis in Figure 22:

1. Training instructs miners to use RAs only as a last resort or as a way station.

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2. Miners perceive that attempting escape is less risky than taking refuge and awaiting

rescue.

Appropriate and effective training is obviously an important component of any successful safety

or health technology introduction. When training for technologies is designed, the creators of the

training content make decisions about what content to include and how the appropriate use of the

technology should be presented. In the case of RAs, the decision was made that miners should be

instructed to use RAs only as a last resort or as a way station to rest, communicate with the

surface, or to switch over SCSRs during escape; this is reflected in multiple training programs

created and distributed by NIOSH [87, 88, 89, 90, 91, 92]. There are two reasons for this

decision. The first is that there are justifiable reasons why escape should be preferred over refuge

and rescue. At the Sago Mine disaster, it was unambiguous that miners would have had a better

chance of survival if an RA had been available; the miners were unable to escape the mine, and

the atmosphere was filled with carbon monoxide. However, scenarios like this are rare among

mine disasters. In most cases, miners would be able to escape, even if they had to do so through

smoke and toxic gases. Clearly, if escape is possible, miners are better off getting out of the mine

than staying in the mine. Although there are these justifiable reasons why escape should be

preferred, there are also scenarios, such as the scenario at Sago, where taking refuge would be

necessary and would be safer than attempting escape. This leads to the first root cause for this

analysis, which is that this engineering control is only able to improve safety under a specific

type of scenario. In other words, since the use of RAs is not universally the safer option in every

mine disaster, the judgement of the miners is needed to select when to use an RA and when not

to.

115

Figure 22: Causal tree analysis for “Miners express strong resistance to using refuge alternatives” (portions shown in

dashed lines are not shown in their entirety because they would duplicate portions of Figure 21; therefore, only the

root causes are shown)

Miners express strong resistance to using refuge alternatives

Training instructs miners to use RAs only as a last resort or as a way station

Justifiable reasons exist for preferring

escape over refuge/rescue

Engineering control improves safety or health

only when used in a specific scenario

Among regulators, mine operators, and researchers,

confidence in RA safety is not

absolute

Risks associated with the use of

RAs were not well understood at the

time of rulemaking

See corresponding portion of causal tree for "Judicial intervention and after-rule time extensions occurred in refuge alternatives

rulemaking"

Biases lead legislators to judge

that immediate action is needed

Biases lead legislators to fail to

recognize indications of technological

immaturity


seriousness of issues identified through

research

Biases lead regulators to judge

that immediate action is needed and to ignore indications

of technological immaturity

Miners perceive that attempting escape is less risky than taking refuge and awaiting rescue

Justifiable reasons exist for preferring

escape over refuge/rescue

Engineering control improves safety or health

only when used in a specific scenario

Fears exist among miners about

entering refuge alternatives

Risks associated with the use of

RAs were not well understood at the

time of rulemaking

See corresponding portion of causal tree for "Judicial intervention and after-rule time extensions occurred in refuge alternatives

rulemaking"

Biases lead legislators to judge


Biases lead legislators to fail to

recognize indications of technological

immaturity


seriousness of issues identified through

research

Biases lead regulators to judge

that immediate action is needed and to


Miners are able to maintain greater

autonomy by attempting escape

than by taking refuge

Biases lead miners to mistrust

interventions

116

Another reason that training programs may have advised using RAs only as a last resort is that

those creating or advising the development of those training programs may have had less than

complete confidence in the ability of RAs to provide a safe environment to await rescue. Again,

this is justifiable since at the time of rulemaking and after, the risks associated with the use of

RAs were not well understood, as has already been discussed. This traces back to the four root

causes shown in Table 13, which were identified through the analysis shown in Figure 21. These

root causes have to do with cognitive biases, such as confirmation bias, the law of the hammer,

availability heuristic, and others as discussed for the previous analysis. The same discussion for

that analysis would apply here.

Aside from the fact that training advises miners to only use RAs as a last resort, the other reason

that miners would be hesitant to use an RA is that they perceive that attempting escape is less

risky than taking refuge and awaiting rescue, which is the right half of Figure 22. There are three

reasons miners might have this perception:

1. Justifiable reasons exist for preferring escape over refuge/rescue.

2. Fears exist about entering refuge alternatives.

3. Miners are able to maintain greater autonomy by attempting escape than by taking refuge.

The first of these has already been discussed and traces to the same root cause discussed above.

The second represents a justifiable fear since the risks associated with entering an RA (for

example, the risk of heat-related illness or the risk of secondary explosion) are significant and are

not well understood. Again, this traces back to root causes already discussed associated with

biases during the legislative and rulemaking procedures. The third, that miners are able to

maintain greater autonomy by attempting escape, represents (at least in part) biases on the part of

117

the miners themselves. These biases may cause a miner to choose to attempt escape even when

taking refuge is the safer course of action. Since this is out of the control of any legislative,

regulatory, or research activities, it is beyond the scope of this study, but should be considered by

those developing training materials or performing research on the human factors of mining safety

and health interventions.

The discussion above traces the causes for the fact that miners express strong resistance to using

RAs to six root causes, four of which can all be attributed to cognitive biases on the part of

legislators, regulators, and researchers who were responsible for making key decisions leading to

the enactment of the regulation, and two of which can be considered inherent limitations or

engineering and administrative controls. These root causes are shown in Table 14.

Table 14: Identified root causes for “Miners express strong resistance to using refuge alternatives”



immaturity





Engineering control improves safety or health only when used in a

specific scenario

Biases lead miners to mistrust interventions

118

5.1.2 Causal Tree Analysis for Case 2: Self-Contained Self-Rescuers

In Section 4.1.2, the recent history on SCSRs was presented, with a particular focus on the CSE

SR-100 SCSR, which was found to experience unacceptably high rates of quality control failure,

as was reported in public notices from NIOSH between 2010 and 2013 [97, 95, 99, 101, 108,

104, 102, 105, 98]. Figure 23 shows a causal tree analysis to find the root causes for this

unacceptably high rate of failures and for why this problem was not identified earlier. Notes and

citations for this analysis are shown in Table 15.

119

Figure 23: Causal tree analysis for "Unacceptably high rate of quality control failures occur for CSE SR-100 self-

contained self-rescuers" (See notes in Table 15)

Unacceptably high rate of quality control failures occur for CSE SR-100 self-contained self-rescuers1

SCSRs are certified despite deficiencies being identified2

Observed failures are incorrectly attributed to degradation in field-

deployed units rather than to problems with manufacture3

Testing is inadequately designed to positively

identify problems with

manufacture4

Biases result in insufficient or

poorly designed experiments

Biases lead to insufficient or

ineffective review of research

findings

Biases lead researchers to

faulty conclusions

despite contradictory data

Observed failures that are identified as problems with manufacture are

discounted as insignificant or as easily corrected5

Explanations provided by

SCSR manufacturers are accepted without

critical review

Biases result in insufficient or


findings

Identified concerns with

certified SCSRs are understated in

public reports6

Biases and political pressures lead researchers to understate the seriousness of

issues identified through research

Biases lead regulators,

researchers, and legislators to

maintain confidence in existing safety

and health technologies

despite indications of

poor performance

Improvements to SCSR technology have not occurred

despite deficiencies

observed in mine disasters7

Technologies other than SCSRs

were seen as a more effective

solution to problems seen at Sago and other

disasters8

Biases lead regulators,

researchers, and legislators to

maintain confidence in existing safety

and health technologies

despite indications of

poor performance

Limited research and development

resources necessitate

prioritization of some technology development and

testing efforts over others

120

Table 15: Notes for causal tree analysis for "Unacceptably high rate of quality control failures occur for CSE SR-

100 self-contained self-rescuers" (See causal tree in Figure 23)

1 See discussion of quality control failures with starter oxygen in Section 4.1.2 and see

public notices concerning failures and investigation in [97, 95, 99, 101, 108, 104, 102, 105,

98]

2 See discussion to prior failure to detect quality control issues in Section 4.1.2. The LTFE

program had identified issues with the performance of CSE SR-100 units in reports

published as far back as 1990 [112] and again in subsequent reports published over nearly

two decades [113, 114, 115, 116, 117, 118, 119].

3 The conclusions of LTFE reports consistently attribute issues identified with tested units to

degradation in the mining environment or to inadequate inspection of the units. The

following quote is from the conclusions of the 2002 LTFE report [117], but very similar

wording appears in all of the other LTFE reports published from 1990 through 2008: “The

results of this study suggest that the large majority of SCSRs that pass their inspection

criteria can be relied upon to provide a safe level of life support capability for mine escape

purposes. However, the mining environment seems to have caused some performance

degradation in the CSE SR-100.”

4 The inadequacy of the LTFE test program for detecting quality control issues is clearly

evident by comparing the sampling procedures for the LTFE testing to the sampling

performed in response to the identification of the quality control problem in 2010. In each

phase of the LTFE, dozens of SCSR units were tested; in contrast, in the 2010-2011 testing

using the quality assurance experimental design, 500 units were tested [100].

5 As early as 1990, manufacturing defects with the starter oxygen in CSE SR-100 SCSRs

were identified. However, these problems were said to have been corrected by the

manufacturer and were thereby discounted. The following quote appears in the conclusions

of the 1990 report of the LTFE, but similar language appears in other LTFE reports:

“Laboratory environmental testing of the SR-100 has uncovered a manufacturing defect in

the burst disk of the oxygen starter bottle and a design problem with the desiccant bag.

Both of these problems have been corrected by the manufacturer.”

6 Although performance problems with SCSR performance were identified through the

LTFE, the conclusions of the public reports from these tests consistently presented the

results in a positive light, including language such as: “The results of this study suggest

that the large majority of SCSRs that pass their inspection criteria can be relied upon to

provide a safe level of life support for mine escape purposes”

7 Investigations of the Sago disaster uncovered apparent deficiencies with SCSRs, including

miners having difficulty breathing while using the units, and miners having difficulty

starting the units, miners removing the units to talk (MSHA and WV Sago investigation

reports). Although these issues might be partially attributable to insufficient expectations

training or insufficient inspections, it is reasonable to conclude that improvements to the

design of the SCSRs might help to address these problems. Despite these indications that

121

improvements to the technology may be needed, changes in mining safety and health

legislation and regulation following the Sago disaster did not force any changes in the

technology.

8 In contrast to changes in SCSR requirements, which were to increase the number of SCSRs

required to be available in the mine and to require caches, changes to the requirements for

communications and tracking systems and refuge alternatives in the MINER Act were

technology-forcing in nature. This is an indication that legislators deemed the development

of these technologies to be a more effective strategy than improvement of SCSRs. In large

part, acceptance of the status quo with respect to SCSRs underlies this decision.

The fact that the potential for widespread quality control failures for these units is especially

troubling when one considers that these units were certified for use in mines jointly by MSHA

and NIOSH despite deficiencies being repeatedly identified through the Long Term Field

Evaluation (LTFE) program that was conducted to evaluate the capabilities of these and other

SCSRs deployed in the field over decades beginning in the 1980s. As was discussed in Chapter

4, the LTFE program had identified issues with the performance of CSE SR-100 units in reports

published as far back as 1990 [112] and again in subsequent reports published over nearly two

decades since then [113, 114, 115, 116, 117, 118, 119]. These performance issues included

insufficient starter oxygen, breathing difficulty, less than rated capacity, and other issues

affecting the safety value of these units.

Despite these limitations being identified, the conclusions of LTFE reports consistently attributed

them to degradation of the units due to the harsh mining environment or to inadequate

inspection. Language such as the following from the conclusions of the 2002 LTFE report [117]

appears in several of the LTFE reports published from 1990 through 2008: “The results of this

study suggest that the large majority of SCSRs that pass their inspection criteria can be relied

upon to provide a safe level of life support capability for mine escape purposes.” So, even when

122

deficiencies with the SCSRs were identified, the potential seriousness of these deficiencies were

understated, which undoubtedly contributed to the continued certification and use of these units.

The discussion above describes the first two proximal causes for the unacceptably high quality

control failure rates in the SCSRs, as shown on the second level of the causal tree in Figure 23:

1. SCSRs are certified despite deficiencies being identified.

2. Identified concerns with certified SCSRs are understated in public reports.

The third proximal cause shown on the figure is that “improvements to SCSR technology have

not occurred despite deficiencies observed in mine disasters.” Since this is unrelated to the first

two causes listed above, it will be discussed separately later.

The reasons that SCSRs are certified despite deficiencies being identified are:

1. Observed failures are incorrectly attributed to degradation in field-deployed units rather

than to problems with manufacture.

2. Observed failures that are identified as problems with manufacture are discounted as

insignificant or as easily corrected.

The first can be traced to root causes on the part of those performing the LTFE program and

preparing the reports from these evaluations. In particular, confirmation bias [254] will have led

the researchers to reinforce any pre-conception they already had that the deficiencies in

performance were due to degradation in the field. Since the same conclusion was published

repeatedly in several subsequent LTFE reports, the bandwagon effect [251] may have led

researchers to go along with this conclusion despite evidence that it might not be correct. In

addition, biases such as the optimism bias [255, 256], and the ostrich effect [256] may have

123

caused researchers to underestimate or ignore the potential negative outcomes of certifying

SCSRs with observed deficiencies.

In these ways, cognitive biases would have played a major role in the false attribution of

observed deficiencies to degradation of units rather than to defects in manufacture. Another way

that biases played a role in this was that they led to inadequate testing of the SCSR units. The

inadequacy of the methods used in the LTFE for detecting quality control issues is clearly

evident by comparing the sampling procedures for the LTFE testing to the sampling performed

in response to the identification of the quality control problem in 2010. In each phase of the

LTFE, dozens of SCSR units were tested; in contrast, in the 2010-2011 testing using the quality

assurance experimental design, 500 units were tested [100]. The sample size and the testing

procedures used in the LTFE were simply not able to conclusively implicate manufacturing

defects in observed poor SCSR performance. The reasons for the insufficiency of the test

methods in this regard can be traced back once again to cognitive biases on the part of the

researchers. Many of the biases already discussed would have caused those designing the study

and those reviewing the research to decide that the methods were sufficient despite the fact that

they could not conclusively test for manufacturing issues. In particular, confirmation bias and the

bandwagon effect were likely involved since, as discussed above, the same conclusions were

repeatedly drawn in several of the LTFE reports over several years.

In some cases, manufacturing defects were implicated in the LTFE reports. However, in these

cases the observed defects were discounted as being easily solved by the manufacturer. As early

as 1990, manufacturing defects with the starter oxygen bottles in CSE SR-100 SCSRs were

identified. However, these problems were said to have been corrected by the manufacturer and

were thereby discounted. The following quote appears in the conclusions of the 1990 report of

124

the LTFE [112], but similar language appears in other LTFE reports: “Laboratory environmental

testing of the SR-100 has uncovered a manufacturing defect in the burst disk of the oxygen

starter bottle and a design problem with the desiccant bag. Both of these problems have been

corrected by the manufacturer.” In this way, the LTFE authors took the word of the SCSR

manufacturers that the issues had been corrected without performing rigorous review of these

claims. This can again be traced to cognitive biases such as confirmation bias, optimism bias,

and the ostrich effect.

So, despite observing and reporting several deficiencies with the SCSR performance, the

seriousness of these issues was understated in public reports. The above discussion shows how

cognitive biases led to this understatement of the deficiencies, which led to the continued

certification and use of these SCSR units.

The third proximal cause shown on the second level of the causal tree in Figure 23 is that

“improvements to SCSR technology have not occurred despite deficiencies observed in mine

disasters.” This refers to the fact that during disasters where SCSRs have been used, the use of

the technology was problematic. In particular, at Sago, miners had difficulty breathing while

using the units, had difficulty starting the units, and removed the units to talk [53, 55]. Although

these issues might be partially attributable to insufficient expectations training or insufficient

inspections, it is reasonable to conclude that improvements to the design of the SCSRs might

help to address these problems. Despite these indications that improvements to the technology

may be needed, changes in mining safety and health legislation and regulation following the

Sago disaster did not force any changes in the technology. Rather, the MINER Act and an

emergency temporary standard only required that an increased number of SCSRs be made

available and that extra units be kept in caches at strategic locations in the mine. Thus,

125

improvements to the functionality of the technology were not forced through the legislation and

regulation.

In contrast, changes to the requirements for communications and tracking systems and refuge

alternatives in the MINER Act were technology-forcing in nature. This is an indication that

legislators deemed the development of these technologies to be a more effective strategy than

improvement of SCSRs. This is due, in part, simply because limited resources necessitate the

prioritization of some R&D efforts over others. However, the decision to prioritize refuge

alternatives and communications and tracking development over improvements to SCSR

technology may also be due to an implicit acceptance of the status quo with respect to SCSRs. In

other words, SCSRs were accepted as a mature and well established technology due to their

long-standing use in mines and the positive conclusions regarding their capabilities as presented

in the LTFE reports. This may have caused legislators and regulators to fail to see the need for

improvement to the technology that was apparent in the difficulties experienced by the Sago

miners. This can be traced to biases such as the optimism bias, which would lead individuals to

believe that the technology would be likely to help miners in a disaster and the ostrich effect,

which would lead individuals to ignore indications that this might not be the case.

The above discussion traces the causes for the fact that unacceptably high rates of quality control

failures occur for CSE SR-100 self-contained self-rescuers to seven root causes, six of which

have to do with cognitive biases at play in decisions made during the testing and certification of

SCSRs as well as in the crafting of legislative and regulatory requirements for this technology.

These root causes are shown in Table 16.

126

Table 16: Identified root causes for "Unacceptably high rate of quality control failures occur for CSE SR-100 self-

contained self-rescuers"

Biases result in insufficient or poorly designed experiments

Biases lead to insufficient or ineffective review of research findings

Biases lead researchers to faulty conclusions despite contradictory data

Biases result in insufficient or ineffective review of research findings



Biases lead regulators, researchers, and legislators to maintain

confidence in existing safety and health technologies despite indications

of poor performance

Limited research and development resources necessitate prioritization of

some technology development and testing efforts over others

5.1.3 Causal Tree Analysis for Case 3: Primary Communications and

Tracking Systems

In Section 4.1.3, the history of the research, development, and diffusion of primary

communications and tracking systems was presented. These technologies were introduced to the

mining industry through a technology-forcing mandate in the MINER Act in response to the

mining disasters of 2006. An examination of this history showed indications that the introduction

of the technology was successful as well as indications that it was not as successful as it may

have been. The fact that primary communications and tracking systems were adopted throughout

the underground coal mining industry without significant time delays or strong resistance is a

good indication that the introduction was successful. On the other hand, the fact that there is no

documented evidence showing that tracking systems achieve a material improvement to safety is

127

an indication that the technology introduction has not been fully successful. Causal analyses for

these two outcomes are presented below.

Causal Tree Analysis of “primary communications and tracking systems are adopted

throughout the underground coal mining industry”

As was discussed in Section 4.1.3, primary communications and tracking systems, which are

node-based wireless systems and leaky feeder systems as opposed to secondary systems such as

through-the-earth and medium frequency, have been adopted by every operating underground

coal mine in the country. This is evidenced in by a review of the emergency response plans

(ERP), which the mines are required to submit to MSHA as mandated by the MINER Act [121].

A causal tree analysis of why this wide-spread adoption has occurred is shown in Figure 24, and

the notes and citations for this analysis are shown in Table 17. As is shown in the second level of

the figure, there are three proximal causes for this success:

1. Systems offer benefits beside safety.

2. Systems developed to an acceptable level of maturity relatively quickly.

3. Enforcement of MINER Act requirements accounted for technological maturity.

The first is relatively self-explanatory – having effective wireless communications and tracking

is useful to mine operators because they can more easily and efficiently coordinate mine

operations. The convenience of having wireless communication quickly and the convenience of

always knowing where miners and equipment are located is an important component of the rapid

adoption. The other two proximal causes require somewhat more discussion. First the relatively

rapid development of the technology will be discussed.

128

Figure 24: Causal tree analysis for "Primary communications and tracking systems are adopted throughout the

underground coal mining industry" (See notes in Table 17)

Primary communications and tracking systems are adopted throughout the underground coal mining industry1

Systems offer benefits

beside safety

Technology provides benefits besides

safety and health

protections

Systems developed to an acceptable level of maturity relatively quickly

Existing technologies from other industries could be

adapted to mining2

MINER Act mandate was designed to

leverage existing

technologies to expedite technology difusion3

Legislators correctly

identified an opportunity

for a technology-

forcing mandate to result in the development

of new or adaptation of

existing technologies

Intramural research by federal agencies provided sound understanding of underlying physics and

other parameters affecting system operation4

MINER Act mandated

federal research on technology

development5


identified the need for

research to achieve

successful results for

technology-forcing mandate

Research agencies

were equipped

with appropriate expertise,

facilities, and resources to

conduct research6

Research agencies correctly identified need for

specialized capabilities and acted to

fulfill the need

Federal research

dollars used to direct

large-scale effort to

develop and adapt

technologies through

extramural research

contracts7

MINER Act mandated

federal research on technology

development5


identified the need for

technology research and

provided adequate

funding to support this

effort

Enforcement of MINER Act requirements

accounted for technological maturity8

MINER Act contained

provisions to allow for less

than fully wireless

communi-cations

systems9

Legislators correctly identified

uncertainty in the ability of industry to meet the

provisions of a technology-

forcing mandate

MSHA recognized that feasible technology

does not exist to provide

truly wireless communi-cations as

required by the MINER

Act

Regulators correctly identified

indications of technological immaturity

129

Table 17: Notes for causal tree analysis for "Primary communications and tracking systems are adopted throughout

the underground coal mining industry" (See causal tree in Figure 24)

1 A review of emergency response plans (ERP) shows that node-based and leaky feeder

wireless communications and tracking systems are implemented at underground mines

throughout the industry [121]. 2 Several of the communications and tracking technologies investigated through the MINER-

Act-mandated NIOSH extramural research program were established technologies that were

already in use in other industries, including node-based communications and RFID tracking

systems. 3 The technology-forcing mandate for communication and tracking systems in the MINER

Act was, in large part, motivated by the observation that wireless communication and

positioning technology was available on the surface but not underground. See the discussion

of this mandate in Section 4.1.3 for more detail. 4 In addition to funding research and development contracts for communication and tracking

systems, as part of the MINER Act mandate, NIOSH conducted extensive intramural

research on communication systems. The bulk of this research focused on understanding and

modeling the propagation of RF signals of various frequencies in underground mines [138,

140, 139, 141, 142, 143]. This research provided system developers with the fundamental

understanding of the operating phenomena to design effective systems as well as with clear

guidelines for system implementation [136, 137]. 5 The MINER Act directed the newly formed Office of Mine Safety and Health Research

(OMSHR) within NIOSH “to enhance the development of new mine safety technology and

technological applications and to expedite the commercial availability and implementation

of such technology in mining environments.” 6 In response to the MINER Act mandate for NIOSH to perform and fund communication and

tracking research and development, the program hired several researchers with expertise in

electromagnetic theory and practical experience with the design and implementation of

communication systems. In addition, laboratory facilities were improved and developed to

enable this research. 7 Between 2006 and 2016, OMSHR awarded 40 extramural research and development

contracts in the topic area of “Emergency Communications and Tracking” [134]. 8 The MINER Act required mines to implement wireless communications systems by June 15,

2009. In the months before this enforcement deadline, MSHA published a program policy

letter (PPL) in which it was stated that “because fully wireless communications technology

is not sufficiently developed at this time, nor is it likely to be technologically feasible by

June 15, 2009, this guidance addresses acceptable alternatives to fully wireless

communication systems.” [128]. This PPL established the acceptance of wired node-based

and leaky feeder systems as acceptable alternatives to fully wireless systems. 9 MINER Act contains the provision: “Where such plan sets forth the reasons such provisions

can not be adopted, the plan shall also set forth the operator's alternative means of

compliance. Such alternative shall approximate, as closely as possible, the degree of

functional utility and safety protection provided by the wireless two-way medium and

tracking system referred to in this subpart.”

130

The relatively rapid development of communications and tracking technologies to a level of

maturity that is acceptable and useful to mine operators was important to the adoption of the

technology. While this development didn’t occur immediately, within a few years of the passage

of the MINER Act, there were systems that were usable and a marked improvement over the

technologies they replaced such as page phones. There are three reasons why the technology was

able to be developed to an acceptable level of maturity so quickly:

First, existing technologies from other industries could be adapted to mining. Technologies such

as node-based communications systems and RFID tracking were already extensively used in

other industries, and more sophisticated leaky feeder technology was already in use in metal/non-

metal mines at the time the MINER Act was passed. Although the underground coal mining

environment presents unique challenges for the implementation of these technologies, it was not

the case that the research and development was starting from the ground up (or rather, down).

This was possible because the MINER Act was written in such a way that it specifically called

for the adaptation of existing technologies, leveraging this opportunity to implement already

mature technologies in a new setting. Because these opportunities did exist, i.e., since it was, in

fact, true that existing wireless communications technologies could be effectively adapted to the

underground mine environment, it can be concluded that legislators correctly identified an

opportunity where a technology-forcing mandate would be effective.

The second reason why communications and tracking technologies were able to be rapidly

developed for underground mining was that there was extensive intramural research by federal

agencies to provide a sound understanding of the underlying physics and other parameters

affecting system operation. Much of the NIOSH intramural research that was conducted in

response the MINER Act was to measure and model the propagation of RF signals in

131

underground mines [138, 140, 139, 141, 142, 143]. Through this research, NIOSH developed and

published guidelines for the design, installation, and use of communications and tracking

systems [136, 137]. This provided the industry with the understanding needed to develop

effective systems and to quickly diffuse this technology throughout the industry. The reasons for

this success can be traced to the root causes that legislators recognized the need for research and

development in order to make the technology-forcing mandate successful and that research

agencies recognized and filled the need for specialized expertise and facilities to conduct this

research and significantly expanded capabilities following the passage of the MINER Act by

hiring several RF experts and improving facilities.

The final, and perhaps most significant, reason that communications and tracking technologies

were developed to maturity rapidly is that extensive extramural research and development efforts

were funded by NIOSH as part of the MINER Act mandate to conduct research on the

technology. Between 2006 and 2016, NIOSH awarded 40 extramural research and development

contracts in the topic area of “Emergency Communications and Tracking” [134]. Although not

all of these resulted in successful products, the overall effect of this massive investment into

R&D was clearly positive. As with the intramural research, this can be traced to the root cause

that legislators correctly recognized that significant research and development would be needed

in order to successfully implement this new technology, and a mandate for this research to be

funded was written into the legislation.

Besides the rapid development of the technology, another proximal cause for the successful

wide-spread adoption of the technology was that enforcement of MINER Act requirements

accounted for the fact that the technology simply was not at a level of maturity to meet the letter

of the requirements of the law – there were not effective communications systems that could

132

provide completely wireless communication between surface and underground. The MINER Act

required mines to implement wireless communications systems by June 15, 2009. In the months

before this enforcement deadline, MSHA published a program policy letter (PPL) in which it

was stated that “because fully wireless communications technology is not sufficiently developed

at this time, nor is it likely to be technologically feasible by June 15, 2009, this guidance

addresses acceptable alternatives to fully wireless communication systems.” [128]. This PPL

established the acceptance of wired node-based and leaky feeder systems as acceptable

alternatives to fully wireless systems.

It was possible for MSHA to be flexible with enforcement of the law in this way because the

MINER Act contains a provision stating that when the provision for a completely wireless

system could not be met, that alternative means of compliance, which “shall approximate, as

closely as possible, the degree of functional utility and safety protection provided by the wireless

two-way medium and tracking system referred to in this subpart.” The inclusion of this language

in the Act shows that legislators correctly identified uncertainty in the ability of the industry to

meet the provisions of their technology-forcing mandate, and therefore provided a level of

flexibility in the enforcement of the law.

With this provision allowing more flexible enforcement, it was up to MSHA to recognize that it

was necessary to take advantage of this flexibility, which they did through the issuance of PPLs

allowing for less than fully wireless systems. This shows that regulators correctly identified the

indications of technological immaturity in fully wireless communications systems and did not

require mines to meet this more rigid requirement.

133

The above discussion has examined the causes for the wide-spread successful adoption of

primary communications and tracking systems and has traced these causes to seven root causes,

six of which are related to legislators, regulators, and researchers correctly assessing the maturity

of the technologies. These root causes are shown in Table 18.

Table 18: Identified root causes for "Primary communications and tracking systems are adopted throughout the

underground coal mining industry"

Legislators correctly identified an opportunity for a technology-forcing

mandate to result in the development of new or adaptation of existing

technologies

Legislators correctly identified the need for research to achieve

successful results for technology-forcing mandate

Legislators correctly identified the need for technology research and

development and provided adequate funding to support this effort

Legislators correctly identified uncertainty in the ability of industry to

meet the provisions of a technology-forcing mandate

Regulators correctly identified indications of technological immaturity

Research agencies correctly identified need for specialized capabilities

and acted to fulfill the need

Technology provides benefits besides safety and health protections

Causal Tree Analysis of “no documented evidence exists showing that tracking systems

achieve a material improvement to safety”

Although the mining industry has adopted communications and tracking technologies in

response to the mandate of the MINER Act, there are, nonetheless, indications that the

technology has not achieved the levels of success that it may have. In particular, there is not

documented evidence that tracking systems achieve a material improvement to safety, meaning

that there is not compelling evidence in the research literature that the performance standards, if

134

achieved, will substantially improve the likelihood of successful escape or rescue and there is not

compelling evidence in the research literature that the tracking systems in use in the industry

meet the performance standards. It is difficult to provide evidence for the lack of research in the

literature; however, the review presented in Section 4.1.3 did not find any evidence that studies

of this type have been performed to show that tracking systems materially improve the chances

of successful escape or rescue. A causal tree analysis of this apparent unsuccessful outcome is

shown in Figure 25, Figure 26, and Figure 27. Notes and citations for this analysis are given in

Table 19.

Below, the causes of the fact that “compelling evidence does not exist to indicate that the

performance standards, if achieved, will substantially improve the likelihood of successful rescue

or escape” is discussed as shown in Figure 26. Following this, the causes for the fact that

“compelling evidence does not exist to indicate that the tracking systems in use in the industry

meet the performance standards” is discussed shown in Figure 27.

Figure 25: Causal tree analysis for "No documented evidence exists showing that tracking systems achieve a

material improvement to safety" (See remainders of causal tree in Figure 26 and Figure 27)

No documented evidence exists showing that tracking systems achieve a material improvement to safety

Compelling evidence does not exist to indicate that the performance standards, if achieved, will substantially improve the likelihood of successful rescue or escape

See remainder of causal tree in subsequent figures

Compelling evidence does not exist to indicate that the tracking systems in use in the industry meet the

performance standards

See remainder of causal tree in subsequent figures

135

Figure 26: Causal tree analysis for "Compelling evidence does not exist to indicate that the performance standards, if

achieved, will substantially improve the likelihood of successful rescue or escape" (Continues from Figure 25; see

notes in Table 19)

Compelling evidence does not exist to indicate that the performance standards, if achieved, will substantially improve the likelihood of successful rescue or escape

Performance standards are not based on a publicly documented an analysis of expected safety gains

Enforcement standards were enacted through mechanisms

that did not require public review as in the rulemaking

process1

Biases lead to insufficient or ineffective review of

research findings

Biases lead regulators to judge that immediate action

is required and to ignore indications of technology

immaturity

Research on the effect of tracking system accuracy on the outcome of escape and rescue

attempts has not been conducted

Test facilities for performing appropriate experiments

were not available

Research on communication system performance is prioritized over research on tracking system performance

Limited research and development resources necessitate prioritization of some technology development and testing

efforts over others

The timeframe for compliance in the MINER Act limits the amount of research that can be completed

Biases lead regulators to judge that immediate action is needed and to ignore indications of technology immaturity

Regulators judged tracking systems to be a mature

technology2

Biases lead regulators to judge that immediate action is required

and to ignore indications of technology immaturity

136

Figure 27: Causal tree analysis for "Compelling evidence does not exist to indicate that the tracking systems in use

in the industry meet the performance standards" (Continues from Figure 25)

Compelling evidence does not exist to indicate that the tracking systems in use in the industry meet the performance standards

Enforcement policy does not provide effective means by which inspectors can check compliance

Enforcement policy was formulated without the support of research on methodological approaches to

quantifying performance

Biases lead regulators to judge that immediate action is needed and to ignore indications of technology

immaturity


Biases lead legislators to judge that immediate action is needed and to ignore indications of technology

immaturity

Research has not been performed to provide independent verification of tracking system

performance

Limited federal research funding is used for quantitative testing of tracking system performance

Test facilities for performing appropriate experiments were not

available

Research on communication system performance is prioritized over research

on tracking system performance

Limited research and development resources necessitate prioritization of some technology development and

testing efforts over others


Biases lead legislators to judge that immediate action is needed and to ignore indications of technology

immaturity

137

Table 19: Notes for causal tree analysis for "No documented evidence exists showing that tracking systems achieve

a material improvement to safety" (See causal trees in Figure 25, Figure 26, and Figure 27)

1 The MINER Act provides a mandate that communications and tracking systems be used in

underground mines, but it does not give details on the required capabilities of these systems.

The performance standards for these systems were enacted through a series of program

policy letters and policy information bulletins [128, 131, 133, 129, 132, 130] rather than

through the normal rulemaking process. 2 In contrast to fully wireless communication systems, tracking systems were judged to be

mature in MSHA’s enforcement of the MINER Act mandate [128].

The reason that there is not compelling evidence that the performance standards, if achieved, will

materially improve the likelihood of successful escape or rescue appears to be that the

performance standards are not based on a publicly documented an analysis of expected safety

gains. While evaluations and demonstrations of tracking systems have been conducted by

NIOSH, MSHA, and others, there is not any study showing what system capabilities would be

needed to enable a miner to successfully escape or to enable a rescue team to successfully find

trapped miners. Clearly, having greater accuracy, faster refresh rates, greater reliability, etc.

would be beneficial to aiding escape and rescue, but it is not clear what all of the performance

metrics should be to evaluate tracking systems and what minimum specifications should be

required for these metrics.

Three factors appear to contribute to this outcome. First, the enforcement of the MINER Act

mandate for tracking systems was accomplished through means other than the normal

rulemaking process. Rather, MSHA issued a series of program policy letters and policy

information bulletins [128, 131, 133, 129, 132, 130] which established the requirements for

accuracy on working sections, in escapeways, and at strategic locations in the mine as well as

establishing other performance metrics such as battery life and component ruggedness. The use

of policy documents rather than rulemaking appears to have been motivated by a sense of

138

urgency to enforce the mandate of the MINER Act. This can be traced to biases which caused

regulators to judge that immediate action was needed and to ignore the fact that compelling

studies of the benefits of tracking systems had not been presented. Biases at play in this decision

were likely the same biases that created the sense of urgency driving refuge alternatives

regulation as discussed in Section 5.1.1, which are presented again in the following.

Cognitive biases such as the availability heuristic [249], availability cascade [250], bandwagon

effect [251], the law of the hammer [252], and the identifiable victim effect [253] may have led

the regulators to conclude that immediate action was needed to respond to the mine disasters that

occurred in 2006.

The availability heuristic [249] is the tendency to overestimate the likelihood of events which

one remembers happening recently or which are more unusual or emotionally charged. In this

case, the disasters at Sago, Darby, and Alma were recent, unusual, and emotionally charged at

the time the tracking requirements was being developed, which contributed to the sense of

urgency for the implementation of the technology. Availability cascade [250] is the cycle by

which propositions which are emotionally charged are frequently repeated in public discourse,

which, by the availability heuristic, increases the emotional charge of these propositions. Before

and following the passage of the MINER Act, the media coverage and public discourse of

mining disasters was intense as has been discussed, which would have reinforced the sense of

urgency to implement tracking technologies. As with the RA regulations, the bandwagon effect

[251] may have also played into this discourse. Finally, the identifiable victim effect [253], the

tendency to respond more strongly to risk when the potential victim of an event is personally

identified rather than a group of unidentified people was at play in these decisions as the personal

stories of mining disaster victims were surely on the minds of regulators.

139

The sense of urgency and the rapid deployment of communications and tracking systems also

limited the amount of research that could be conducted on the needed capabilities of tracking

systems to enable successful escape or rescue. This is shown as the second cause on the second

level of Figure 26. This is traced to three root causes. First, the facilities to conduct the tests were

not available to federal researchers. Second, limited resources caused researchers to prioritize

communications research over tracking research. And finally, the same biases that caused

regulators to judge that immediate action was needed also caused legislators to judge that

immediate action was needed when they passed the MINER Act.

Figure 27 shows the analysis for the causes of why compelling evidence does not exist to

indicate that the tracking systems in use in the industry meet the performance standards. As with

the previous analysis, one reason is the fact that research had not been conducted, which traces to

the same root causes discussed above: the facilities to conduct the testing were not available,

limited resources led to prioritization of communications research over tracking research, and

biases caused legislators to judge that immediate action was needed while ignoring indications of

technological immaturity.

The other causal chain shown on the left side of Figure 27 has to do with the enforcement policy

for tracking systems not including clearly defined, quantitative methods by which inspectors can

evaluate the performance of tracking systems. While policy guidance has been issued to aid

inspectors in evaluating these systems [133], the guidance does not provide a detailed method by

which inspectors can systematically and quantitatively check the accuracy, reliability, or other

performance metrics. This can reasonably be expected to lead to inconsistencies in how these

evaluations are performed from inspector to inspector, which decreases the confidence that can

be placed in the ability of tracking systems to meet the established performance criteria. The lack

140

of detailed guidance is likely due again to the sense of urgency that existed around the creation

of these policies and around the passage of the MINER Act. The root causes for this are once

again the same biases that have caused legislators and regulators to judge that immediate action

is needed and to ignore indications that technologies are not mature.

The above discussion and analysis has identified the root causes for the unsuccessful outcome

“no documented evidence exists showing that tracking systems achieve a material improvement

to safety.” Six root causes have been identified, four of which have to do with cognitive biases in

decision making by legislators, regulators, and researchers. These root causes are shown in Table

20.

Table 20: Identified root causes for "No documented evidence exists showing that tracking systems achieve a

material improvement to safety"


Biases lead regulators to judge that immediate action is required and to

ignore indications of technology immaturity



Biases lead legislators to judge that immediate action is needed and to


Test facilities for performing appropriate experiments were not available

Limited research and development resources necessitate prioritization of

some technology development and testing efforts over others

141

5.1.4 Causal Tree Analysis for Case 4: Proximity Detection Systems

In Section 4.1.4, a summary of the recent history of proximity detection systems for underground

coal mining equipment was presented. In this history, one indication that the technology has

achieved an unsuccessful outcome is the occurrence of electromagnetic interference (EMI)

between the continuous personal dust monitor and proximity detection systems, the result of

which is to render the proximity detection system inoperable. A root cause analysis for why this

outcome was not predicted and prevented is shown in Figure 28.

Figure 28: Causal tree analysis for "Electromagnetic interference (EMI) between continuous personal dust monitors

and proximity detection systems effectively render the proximity detection system temporarily inoperable"

Electromagnetic interference (EMI) between continuous personal dust monitors and proximity detection systems effectively render the proximity detection system temporarily inoperable

Proximity detection systems and personal dust monitors are not

designed for electromagnetic

compatibility (EMC)

Standards for EMC do not exist for the

underground mining industry

Biases lead to an acceptance of the status quo with

respect to recognized deficiencies in safety and health standards

Research failed to identify the potential

for EMI

Laboratory and field testing of proximity detection systems was not conducted

under conditions that would show EMI

Biases result in poorly designed or

insufficient experiments

Reports from mine operators that systems are not operating properly are not attributed to EMI

A high level of confidence was

placed in manufacturers' engineering of

systems

Biases lead to insufficient review of

research findings

Biases lead to a lack of independent assessment of technologies' capabilities

Reports of system malfunction are

incorrectly attributed to innocuous causes

such as operator misunderstanding/

misinterpretation of system functionality

or poor system calibration/

configuration

Biases lead regulators to ignore indications

of technology immaturity

Biases lead researchers to ignore

indications of technology immaturity

142

Three reasons that the potential for EMI between the personal dust monitor and the proximity

detection system was not predicted and prevented are:

1. Proximity detection systems and personal dust monitors are not designed for

electromagnetic compatibility (EMC).

2. Research failed to identify the potential for EMI.

3. Reports from mine operators that systems are not operating properly are not attributed to

EMI.

Standards for EMC design of electronic systems do not apply to devices used underground.

Since these standards do not exist, they obviously weren’t applied in the design of the personal

dust monitor and the proximity detection systems. The use of such standards would have placed

upper limits on the electromagnetic emission of each device and lower limits on the

susceptibility of each device to interference, which would have prevented this occurrence of

EMI. It is reasonable to assume that through the years, several people in research and regulatory

agencies recognized the need for such standards, but action was never taken to implement such

standards. It is also reasonable to conclude that cognitive biases played a role in this inaction by

contributing to an acceptance of the status quo with respect to recognized deficiencies in safety

and health standards. Biases that may be at play here likely include confirmation bias [254],

which would have led people to reinforce their notions that standards were not needed, optimism

bias [255, 256], which would have led people discount the possibility that EMI could occur, and

the ostrich effect [256], which would have led people to ignore indications that the lack of

standards created the potential for EMI.

143

The failure of agencies performing research on proximity detection and personal dust monitors to

identify the potential for EMI was due to the fact that studies on the potential for EMI involving

these devices simply was not conducted. Although experts in electromagnetics were involved in

the research at NIOSH, experiments on the potential for EMI did not occur. This shows that

biases, such as those described above led resulted in poorly designed or insufficient experiments.

The final proximal cause for the failure to prevent EMI was that reports from mine operators that

systems were not operating properly were not attributed to EMI. During the development and

diffusion of proximity detection systems, mine operators reported to NIOSH as well as to MSHA

that the systems were not operating properly or consistently. It now seems that many of these

instances may have been due to EMI; however, this was not identified at the time because

alternative explanations such as operator misunderstanding/misinterpretation of system

functionality or poor system calibration/configuration were believed to have been the true cause

of the reports of malfunction. Although there was no evidence to support these explanations, they

are relatively innocuous and were simply assumed to be true. A high level of trust had also been

placed in the engineering of the systems, with the underlying assumption that the manufacturers

would have properly designed their systems to prevent EMI. This was clearly a faulty

assumption given the lack of EMC standards. In all of these judgements, the same biases

discussed above (confirmation bias [254], optimism bias [255, 256], and the ostrich effect [256])

may have been involved.

The analysis and discussion above has traced the causes for the fact that electromagnetic

interference (EMI) between continuous personal dust monitors and proximity detection systems

effectively render the proximity detection system temporarily inoperable” to six root causes, all

144

of which have to do with biases during key decisions by researchers and regulators. These root

causes are shown in Table 21.

Table 21: Identified root causes for "Electromagnetic interference (EMI) between continuous personal dust monitors

and proximity detection systems effectively render the proximity detection system temporarily inoperable"

Biases lead to an acceptance of the status quo with respect to recognized

deficiencies in safety and health standards

Biases lead to insufficient review of research findings

Biases lead to a lack of critical assessment of technologies' capabilities

Biases lead regulators to ignore indications of technology immaturity

Biases lead researchers to ignore indications of technology immaturity

Biases result in poorly designed or insufficient experiments

5.1.5 Causal Tree Analysis for Case 5: LED Cap Lamps

Section 4.1.5 provided a history of the development and diffusion of mine cap lamp technology

and a more focused history of the recent development and diffusion of LED cap lamp

technology. LED cap lamps have been rapidly and voluntarily adopted throughout the

underground mining industry. A causal tree analysis for why this adoption was so successful is

shown in Figure 29. This rapid adoption can be attributed to the fact that LED cap lamps offer

several benefits related to energy efficiency, operating cost, compact size, and the convenience

of not having a corded light with a belt-worn battery. These benefits were discussed in more

detail in Section 4.1.5. The safety benefits of the technology have also been demonstrated, but

this was not a driving factor in the adoption of the cap lamps. The adoption of the new

technology of LED cap lamps was also enabled by the fact that regulatory and legislative

standards for cap lamps do not prescribe a specific technology to be used, but rather provide

145

performance-based specifications that must be met. Since these standards did not preclude the

use of new technologies, they did not hinder the adoption of LED cap lamps. The root causes

identified for the successful adoption of LED cap lamps are shown in Table 22. Two of the three

root causes have to do with regulators and legislators enabling new technologies to be introduced

by including flexibility in the safety mandate for mine lighting.

Figure 29: Causal tree analysis for "LED cap lamps are rapidly and voluntarily adopted by mine operators

throughout the underground mining industry"

Table 22: Identified root causes for "LED cap lamps are rapidly and voluntarily adopted by mine operators

throughout the underground mining industry"

Legislators correctly identified the need for flexibility in regulations to

allow for technology development

Regulators correctly identified the need for flexibility in regulations to



LED cap lamps are rapidly and voluntarily adopted by mine operators throughout the underground mining industry

LED cap lamps offer benefits besides than safety and health

improvements

Technology provides benefits besides safety and health

protections

Regulatory standards for cap lamps allow for alternative cap

lamp technology to be used

Regulators correctly identified the need for flexibility in regulations to allow for technology development

Legislative standards for cap lamps allow for alternative cap

lamp technology to be used

Legislators correctly identified the need for flexibility in regulations to allow for technology development

146

5.2 Causal Tree Analyses for Health Interventions

In Section 4.2, historical summaries of the research, development, and diffusion of new noise

control technologies for mining equipment was provided with a particular focus on underground

coal mining equipment including continuous mining machines and roof bolting machines, which

had been identified as the pieces of equipment with the greatest occurrence of noise

overexposure. The development of this technology was driven, in large part, by the promulgation

of new hearing loss prevention regulations by MSHA in 1999. An analysis of the MSHA data on

noise exposure surveys, it was noted that the average noise dose experienced by continuous

mining machine operators has steadily decreased since the promulgation of the regulation, while

the dose for roof bolting machine operators has remained relatively flat. This is an indication

that, somehow, the technology-forcing mandate for new noise controls has apparently been more

successful for the continuous mining machines than it has for the roof bolting machines.

In the following sections, causal tree analyses for the successful outcome with continuous mining

machine noise controls and for the unsuccessful outcome with roof bolting machines will be

presented.

5.2.1 Causal Tree Analysis for Noise Controls for Case 6: Continuous Mining

Machines

Noise exposures for continuous mining machine operators have steadily dropped since 1999

when MSHA passed a technology-forcing regulation, which in part, required all feasible noise

controls to be used. A causal tree analysis for why these exposures have decreased is shown in

Figure 30, and notes and citations for this analysis are given in Table 23.

147

Figure 30: Causal tree analysis for "Continuous mining machine noise controls achieve a demonstrated reduction in

noise exposure for operators" (See notes in Table 23)

Continuous mining machine noise controls achieve a demonstrated reduction in noise exposure for operators1

Mines utilize engineering noise controls to reduce noise exposure

Effective noise controls are available as standard equipment

or as options from mining machinery

OEM2

Implementation of noise controls offer

benefits besides safety and health3


Noise controls are developed and

demonstrated through collaboration between researchers and OEM4

Researchers develop effective partnerships with industry in order to facilitate the best

solutions and to better diffuse research

findings into practice

Mine operators purchase equipment with noise controls

Technology provides benefits besides safety

and health protections3

Technology increases capital cost, but does not increase operating

cost

Noise controls have minimal impact on

equipment operation

During research and development, the impact on mining

operations was considered

Noise controls are deemed technically and administratively

achievable by regulators5

Effectiveness of intervention was

successfully demonstrated in field trials under operating

conditions

Mines utilize administrative noise controls to reduce

noise exposure

Effective means of isolating workers

from hazards through administrative controls exist

Administrative noise controls are deemed

administratively achievable by

regulators5

Regulators correctly recognized the need for a combination of

engineering and administrative

controls

Noise regulation allows mine operators to use a combination of engineering and

administrative controls at their

discretion6

Regulatory requirement is a

written as a performance-based

standard

148

Table 23: Notes for causal tree analysis for "Continuous mining machine noise controls achieve a demonstrated

reduction in noise exposure for operators" (See causal tree in Figure 30)

1 See discussion on continuous mining machine operator noise dose surveillance data in

Section 4.2.1.

2 Joy Mining Machinery, now owned by Komatsu, modified their facilities to produce dual-

sprocket chains and coated flight bars for their continuous mining machines [228, 226, 225].

3 The dual-sprocket chain technology was shown to reduce wear on the chain and sprockets

and to lengthen the life of the components [228, 226, 225].

4 Throughout the development of the noise controls, collaborative research and development

efforts were performed between NIOSH and Joy Mining Machinery [225].

5 See MSHA Program Information Bulletin No. P14-02 (Reissue of P08-12),

“Technologically Achievable, Administratively Achievable, and Promising Noise Controls”

[229].

6 Per the noise regulation, when the 90dBA PEL is exceeded, the mine operator is required to

implement feasible engineering and administrative controls to reduce exposure to the PEL.

While the feasibility of the controls is determined by MSHA as the feasibility for the

particular mine in question to implement the control, it is up to the mine operator to select

whether engineering controls, administrative controls, or some combination of the two is

used [220].

This reduction in exposures can be attributed to two primary causes: the use of administrative

noise controls and the use of engineering noise controls. It is important to note that since the

regulations do not give credit for hearing protectors and since the noise exposure surveys

conducted by inspectors do not take the attenuation provided by hearing protectors into

consideration; therefore, these exposures are independent of any additional benefit that may have

been achieved over the same period by increased use of ear plugs or ear muffs. It is also

important to note that mining operations have changed significantly over the last two decades. In

particular, the number and size of underground coal mining operations have decreased as market

and regulatory conditions have changed. This is a confounding factor to this analysis since it is

possible that the changing nature of mine operations also played a role in the changing noise

149

exposure. This effect would be difficult to isolate and quantify, and no attempt has been made to

do so here.

The reasons why mine operators have utilized engineering noise controls can be linked to three

causes:

1. Effective noise controls are available as standard equipment or as options from mining

machinery OEM.

2. Mine operators purchase equipment with noise controls.

3. Noise controls are deemed technically and administratively achievable by regulators.

The noise controls for continuous mining machines that have been listed as feasible in the

MSHA PIB [229] include the dual-sprocket conveyor chain and polyurethane-coated conveyor

flights, both of which were successfully demonstrated to be effective in field tests and both of

which are now offered either as standard equipment or as options on all new continuous mining

machines from Joy Mining Machinery, now owned by Komatsu [228, 226, 225]. The fact that

the manufacturer modified their facilities to offer these products as well as the fact that mine

operators purchased these products is in part due to the fact that they provide benefits besides

just reducing noise exposure; the dual-sprocket chain technology was shown to reduce wear on

the chain and sprockets and to lengthen the life of the components [228, 226, 225]. The adoption

of the technologies is also due, in part, to the effective collaboration that occurred between

federal researchers at NIOSH and the equipment manufacturers to develop and test these

systems. The nature of the noise controls also play a part in the adoption by mine operators; the

controls are installed on the conveyor chain and do not affect the normal operation of the

150

machine or change the way the equipment operator does their job, which can be attributed to the

fact that the impact on mine operations was considered during the development of these controls.

The adoption of administrative controls for continuous mining machines is also influenced by the

design of the machine and the nature in which it is operated. Continuous mining machines are

remote-controlled pieces of equipment, which grants greater flexibility in when the machine

operator can be positioned in order to avoid especially noisy locations. The use of these

administrative controls was enabled by the listing of the controls in the MSHA PIB [229] and by

the flexibility allowed in the regulation to use a combination of administrative and engineering

controls. Per the noise regulation, when the 90dBA PEL is exceeded, the mine operator is

required to implement feasible engineering and administrative controls to reduce exposure to the

PEL. While the feasibility of the controls is determined by MSHA as the feasibility for the

particular mine in question to implement the control, it is up to the mine operator to select

whether engineering controls, administrative controls, or some combination of the two is used

[220]. This flexibility reflects the regulators correct assessment that a combination of

engineering controls and administrative controls would be needed to address noise

overexposures and that the use of a performance-based standard was most appropriate.

The analysis and discussion above traced the causes of the demonstrated reduction in noise

exposure for continuous mining machine operators since the promulgation of a technology-

forcing mandate for noise controls by MSHA in 1999. Eight root causes were identified, five of

which have to do with regulators and researchers engaging effectively in the development and

diffusion of the technologies. These root causes are shown in Table 24.

151

Table 24: Identified root causes for "Continuous mining machine noise controls achieve a demonstrated reduction in

noise exposure for operators"

Regulators correctly recognized the need for a combination of

engineering and administrative controls

Researchers develop effective partnerships with industry in order to

facilitate the best solutions and to better diffuse research findings into

practice

During research and development, the impact on mining operations was

considered

Effectiveness of intervention was successfully demonstrated in field

trials under operating conditions

Regulatory requirement is a written as a performance-based standard

Effective means of isolating workers from hazards through

administrative controls exist


Technology increases capital cost, but does not increase operating cost

5.2.2 Causal Tree Analysis for Noise Controls for Case 7: Roof Bolting

Machines

In contrast to continuous mining machine operators, the average noise dose for roof bolting

machine operators has remained relatively flat since the promulgation of the new MSHA noise

regulation in 1999, and through the resulting efforts to introduce engineering and administrative

noise controls for this equipment. A causal tree analysis of why exposures with this machine

have not decreased as they did with the continuous mining machine is shown in Figure 31. Notes

and citations for this analysis are given in Table 25.

152

Figure 31: Causal tree analysis for "Roof bolting machine noise controls fail to achieve a demonstrated reduction in

noise exposure for operators" (See notes in Table 25)

Table 25: Notes for causal tree analysis for "Roof bolting machine noise controls fail to achieve a demonstrated

reduction in noise exposure for operators" (See causal tree in Figure 31)

1 See discussion on roof bolting machine operator noise dose surveillance data in Section

4.2.2. 2 Controls were developed in collaboration between NIOSH and companies including Corry

Rubber Corporation and Kennametal, Inc. These controls included a collapsible drill steel

enclosure [234] and isolators for the drill bit and chuck [236]. 3 See MSHA Program Information Bulletin No. P14-02 (Reissue of P08-12),

“Technologically Achievable, Administratively Achievable, and Promising Noise Controls”

[229].

Roof bolting machine noise controls fail to achieve a demonstrated reduction in noise exposure for operators1

There is limited utilization of

engineering noise controls

Noise controls are supplied by a

third-party manufacturer

rather than being offered by mining machinery OEM2

Nature of noise control does not

allow it to be offered by the

OEM

Nature of equipment

operation and design limits

design of engineering

controls

Mine operators do not purchase and implement noise

controls

Noise controls have significant negative impacts

on equipment operation

Nature of equipment



controls

Noise controls increase operating

cost

Technology increases capital

and operating costs

Noise control is implemented as a

consumable

Nature of equipment



controls

Noise controls are not deemed technically

achievable by regulators3

Effectiveness of intervention was not successfully demonstrated in field trials under

operating conditions

There is limited utilization of

administrative noise controls

Effective means of isolating workers

from hazards through

administrative controls do not

exist

153

Whereas the continuous mining machine apparently experienced decreases in exposure due to

the adoption of engineering and administrative controls, there was limited adoption of such

controls for roof bolting machines. The limited adoption of administrative controls can be

attributed primarily to a fundamental difference in the design of these two machines and the

means by which the machines are operated. Continuous mining machines are remote-controlled,

which allows miners to position themselves more flexibly. On the other hand, roof bolting

machines are operated by a miner standing directly adjacent to where the holes are being drilled,

which is the greatest noise source for the machine. Miners must stand in this location in order to

operate the machine properly, which greatly limits the use of administrative controls.

The reasons that the engineering controls for the roof bolting machines have not been adopted

are also in direct contrast with the reasons that controls were adopted for continuous mining

machines. Whereas continuous mining machine noise controls were included as standard or

optional equipment by equipment manufacturers, the noise controls for roof bolting machines

were offered as consumable components (drill bit and drill steel components) by third-party

suppliers. This placed a greater burden on mine operators to utilize the controls since it was not

simply a matter of purchasing a new piece of equipment with the controls installed; the mine

operator had to continuously stock the controls and ensure that they were being used. This can be

traced to the root cause that the nature of the equipment design limited the type of noise controls

that could be used – since the noise sources is the drill steel and the drill bit, the possible set of

controls that could be designed is limited. Another factor that apparently limited the adoption of

these controls was that the controls increase operating cost and have a significant impact on the

operation of the machine. Again, this can be traced to the fact that the noise controls that could

be designed for a roof bolting machine was limited by the nature of the noise sources for this

154

machine and the manner in which the machine is operated. In other words, the development of

effective noise controls for a roof bolting machine is simply a more difficult engineering

challenge than the development of effective noise controls for a continuous mining machine.

The challenges associated with developing controls for this machine also led to the failure of

researchers to successfully demonstrate the effectiveness of the controls through field trials and

to have the controls listed as technically achievable in the MSHA PIB (with the exception of the

drill bit isolator, which was demonstrated and listed).

In summary, the causes for the lack of exposure reduction for roof bolting machine operators was

traced to four root causes, which are shown in Table 26. All of these root causes reflect the

difficulty of the engineering challenges involved with developing controls for this machine,

which is not an indication of any shortcoming in the regulatory or research processes involved.

Table 26: Identified root causes for "Roof bolting machine noise controls fail to achieve a demonstrated reduction in

noise exposure for operators"

Effectiveness of intervention was not successfully demonstrated in field

trials under operating conditions

Effective means of isolating workers from hazards through

administrative controls do not exist

Technology increases capital and operating costs

Nature of equipment operation and design limits design of engineering

controls

155

5.3 Generalization of Causal Tree Analysis Results

The preceding sections have presented causal tree analyses for three indications of successful

outcomes for new safety and health technologies in mining and for six indications of

unsuccessful outcomes for new safety and health technologies in mining. The identified root

causes associated with the successful outcomes are summarized in Table 27, and the identified

root causes for the unsuccessful outcomes are summarized in Table 28. In this section,

commonalities between these identified root causes will be identified and the implications for

future efforts to introduce new safety and health technologies will be discussed.

Table 27: Identified root causes for indications of safety and health technology mandate success

Identified Root Causes

Primary communications and

tracking systems are adopted

throughout the underground

coal mining industry



technologies

Legislators correctly identified the need for research to achieve successful

results for technology-forcing mandate



Legislators correctly identified uncertainty in the ability of industry to meet the

provisions of a technology-forcing mandate


Research agencies correctly identified need for specialized capabilities and

acted to fulfill the need


LED cap lamps are rapidly

and voluntarily adopted by

mine operators throughout

the underground mining

industry

Legislators correctly identified the need for flexibility in regulations to allow

for technology development

Regulators correctly identified the need for flexibility in regulations to allow



Continuous mining machine

noise controls achieve a

demonstrated reduction in

noise exposure for operators

Regulators correctly recognized the need for a combination of engineering and

administrative controls

Researchers develop effective partnerships with industry in order to facilitate

the best solutions and to better diffuse research findings into practice


considered

Effectiveness of intervention was successfully demonstrated in field trials

under operating conditions


Effective means of isolating workers from hazards through administrative

controls exist



156

Table 28: Identified root causes for indications of safety and health technology mandate failure

Identified Root Causes

Judicial intervention and

after-rule time extensions

occurred in refuge

alternatives rulemaking



immaturity



Biases lead regulators to judge that immediate action is needed and to ignore


Miners express strong

resistance to using refuge

alternatives



immaturity





Engineering control improves safety or health only when used in a specific

scenario


Unacceptably high rate of

quality control failures occur

for CSE SR-100 self-

contained self-rescuers




Biases result in insufficient or ineffective review of research findings



Biases lead to acceptance of status quo despite observed deficiencies

Limited research and development resources necessitate prioritization of some

technology development and testing efforts over others

No documented evidence

exists showing that tracking

systems achieve a material

improvement to safety


Biases lead regulators to judge that immediate action is required and to ignore




Biases lead legislators to judge that immediate action is needed and to ignore





Electromagnetic interference

(EMI) between continuous

personal dust monitors and

proximity detection systems

effectively render the

proximity detection system

temporarily inoperable



Biases lead to insufficient review of research findings




Biases result in poorly designed or insufficient experiments

Roof bolting machine noise

controls fail to achieve a

demonstrated reduction in

noise exposure for operators

Effectiveness of intervention was not successfully demonstrated in field trials



controls do not exist


Nature of equipment operation and design limits design of engineering controls

157

Several of the root causes pertain to actions or decisions made by legislators, regulators, and

researchers. Re-organizing the lists of root causes by the relevant group is useful. This is done in

Tables 29 and 30 for the successful and unsuccessful outcomes, respectively. Examining the

tables above, a number of similarities begin to become apparent. Several of the root causes that

contributed to successful outcomes for new safety and health technologies (Tables 27 and 29)

relate to the assessment of technological maturity. It seems to be the case that, in order for the

introduction of a new safety and health technology mandate to be successful, legislators and

regulators need to have an accurate assessment of the capabilities of the technology and an

accurate assessment of the effort that would be required to develop and implement the

technology, as well as a recognition of any uncertainty involved in either of those assessments.

In contrast, several of the root causes that contributed to unsuccessful outcomes (Tables 28 and

30) relate to cognitive biases causing regulators, legislators, and researchers to draw flawed

conclusions about the maturity of a technology or to ignore indications of technological

immaturity.

Other root causes for successful outcomes relate to the success of research to definitively

demonstrate the efficacy of the interventions and to the effective partnership between researchers

and industry to design and deploy interventions in a way that minimizes the impact on mine

operations and/or offers some benefit besides safety and health. Again, by way of contrast, some

of the root causes for unsuccessful outcomes relate to an increased burden on mine operators,

either in the form of increased costs or some hindering of mine operations.

158

Table 29: Root causes for indications of technology mandate success grouped by groups primarily involved

Root causes of

technology success

that pertain

primarily to

legislators



technologies

Legislators correctly identified the need for research to achieve successful

results for technology-forcing mandate



Legislators correctly identified uncertainty in the ability of industry to meet the

provisions of a technology-forcing mandate

Legislators correctly identified the need for flexibility in regulations to allow


Root causes of

technology success

that pertain

primarily to

regulators


Regulators correctly identified the need for flexibility in regulations to allow


Regulators correctly recognized the need for a combination of engineering and

administrative controls


Root causes of

technology success

that pertain

primarily to

researchers

Researchers develop effective partnerships with industry in order to facilitate

the best solutions and to better diffuse research findings into practice

Research agencies correctly identified need for specialized capabilities and

acted to fulfill the need

Effectiveness of intervention was successfully demonstrated in field trials



considered

Other root causes of

technology success



controls exist


159

Table 30: Root causes for indications of technology mandate failure grouped by groups primarily involved

Root causes of

technology failure

that pertain

primarily to

legislators



immaturity

Biases lead legislators to judge that immediate action is needed and to ignore


Root causes of

technology failure

that pertain

primarily to

regulators




Root causes of

technology failure

that pertain

primarily to

researchers










Effectiveness of intervention was not successfully demonstrated in field trials


Other root causes of

technology failure

Engineering control improves safety or health only when used in a specific

scenario


Biases lead to acceptance of status quo despite observed deficiencies





controls do not exist


Nature of equipment operation and design limits design of engineering

controls

160

The list of root causes for successful outcomes were simplified by combining similar items into

the following ten items:

1. Legislators correctly identified an opportunity for a technology-forcing mandate to result

in the development of new or adaptation of existing technologies

2. Legislators correctly identified the need for research and development to achieve

successful results for a technology-forcing mandate

3. Legislators correctly identified uncertainty in the ability of industry to meet the

provisions of a technology-forcing mandate and permitted flexibility in compliance to


4. Regulators correctly identified indications of technological immaturity

5. Regulators correctly identified the need for flexibility in regulations to allow for

technology development

6. Regulatory requirements are written as performance-based standards

7. Researchers develop effective partnerships with industry in order to facilitate the best

solutions and to better develop research findings into practical interventions that can be

effectively diffused

8. Research agencies correctly identified need for specialized capabilities and acted to fulfill

the need

9. Effectiveness of intervention was successfully demonstrated in field trials under

operating conditions

10. Interventions can be designed that have minimal impact on mine operations and/or offer

some benefit aside from safety and health protections

161

It is not necessary that all of these be present, but the analysis shows that at least some of these

factors contributed in each of the successful outcomes analyzed. Although not all of these are

applicable to every technology introduction, this analysis shows these factors to contribute to

successful outcomes.

The root causes for unsuccessful outcomes can similarly be simplified to the following eight

items:

1. Biases lead legislators to judge that immediate action is needed and to ignore indications


2. Biases lead regulators to judge that immediate action is needed and to ignore indications


3. Biases and political pressures lead researchers to ignore or to understate observed

indications of technological immaturity identified through research

4. Despite the best efforts of researchers and developers, effective interventions either

cannot be developed or cannot be demonstrated to be effective due to engineering

challenges or economic constraints

5. Biases lead to an acceptance of the status quo with respect to recognized deficiencies in

safety and health standards or technologies

6. Cultural forces and cognitive biases among miners lead to a mistrust of new interventions

7. Biases result in insufficient or poorly designed experiments

8. Biases result in insufficient or ineffective review of research

162

The presence of one, or even several, or these factors would not guarantee an unsuccessful

outcome for a new safety or health technology mandate, but at least a few of these factors were

present in each of the unsuccessful outcomes analyzed.

These root causes demonstrate the need to find ways of overcoming biases that affect the

decisions made by regulators, researchers, and legislators and to ensure the objectivity of these

groups. These biases can lead to several intermediate outcomes that further contribute to

unsuccessful outcomes, such as:

• Regulators or legislators may fail to confirm that, if successfully implemented, new

standards would achieve a material improvement to safety and health

• Regulators or legislators may fail to implement effective means of checking and

quantifying compliance with a new standard

• Regulators or legislators may act with an unfounded degree of urgency to implement new

mandates without first confirming the readiness of the technology needed to meet the

mandate

• Researchers may overstate the maturity of technologies despite evidence of deficiencies

• Researchers may fail to identify the potential for unintended consequences that can occur

in the operating conditions at the mine

These outcomes can lead to the enactment of rules which mandate the use of technologies that

have not been demonstrated to be effective or that have observed deficiencies; an example of this

is the mandate for refuge alternatives despite observed deficiencies in the chambers. They can

also lead to the certification and use of technologies that are defective and do not meet the intent

or letter of safety and health regulations; an example of this is the continued certification and use

163

of SR-100 SCSRs despite observed deficiencies through the LTFE. Finally, these causes can lead

to the implementation of technologies that, although they perform well and deliver the desired

safety or health benefit, introduce some unintended consequence that diminishes safety in some

other way; an example of this is electromagnetic interference between the personal dust monitor

and proximity detection systems, whereby the introduction of an effective health intervention

caused the unintended consequence of disabling an effective safety intervention.

There is a need to maintain objectivity throughout the process of writing, reviewing, passing, and

enforcing new safety and health mandates as well as throughout the process of researching,

developing, deploying, and using new safety and health technologies. In particular, it is

necessary to actively identify indications of technological immaturity in an objective manner.

When indications of technological immaturity are identified, efforts should be made to improve

the technology, but efforts should also be made to appropriately modify existing or proposed

safety and health regulations or legislation. A means of assessing when a new safety or health

technology has matured to the point that it can proceed in development, diffusion, or regulation

is needed.

In the next chapter, recommendations for how objectivity can be better assured during the

crafting of new safety and health regulations or legislation and during the research and

development of new safety and health interventions will be presented.

164

Chapter 6: Bowtie Analysis of Mandates for Immature

Safety and Health Technologies

The previous chapter presented a series of root cause analyses for several successful and

unsuccessful outcomes for safety and health technology mandates in the mining industry. The

result of each of these analyses was the identification of root causes for the outcome. These root

causes were then compiled and compared to find a set of ten generalized root causes for

successful outcomes and a generalized set of eight root causes for unsuccessful outcomes. The

root causes for the successful outcomes represent desirable conditions to enable and foster the

development and diffusion of effective safety and health technologies whereas the root causes

for the unsuccessful outcomes represent threats to the successful development and diffusion of

effective technologies.

Left unchecked, these threats can lead to the enactment of legislation or regulation that mandates

the use of safety and health technologies that are immature, meaning that these technologies have

not been adequately developed or demonstrated and may lead to undesirable consequences. In

this chapter, bowtie analysis is used to develop recommendations for how mining safety and

health regulatory agencies and research agencies can attempt to avoid the enactment of a

mandate for an immature safety or health technology and, in the event that such a mandate is

enacted, to mitigate the undesirable consequences of the mandate. This bowtie analysis will be

presented in the next section along with general recommendations for mining safety and health

regulatory agencies and research agencies. In Chapter 7, a more detailed discussion of how these

recommendations could be implemented is presented.

165

As was described in Chapter 3, bowtie analysis is a method typically used to systematically

consider the causes and outcomes of some hazardous event and to develop controls to prevent

the causes from leading to the release of the hazard as well as recovery measures to mitigate and

to decrease the severity of the consequences it that hazard is realized. In this study, bowtie

analysis is adapted to develop strategies to prevent the enactment of a safety or health technology

mandate for an immature technology and to mitigate the undesirable consequences of such a

mandate. Rather than performing this analysis for each of the safety and health technologies

considered in Chapters 4 and 5, a generalized case was studied. This simplified the analysis and

also enabled the development of more generalizable conclusions and recommendations. This

bowtie analysis for the generalized case of an immature safety or health technology mandate is

presented here.

6.1 Threats and Outcomes Associated with the Enactment of a

Mandate for an Immature Safety or Health Technology

The threats in this bowtie analysis are the generalized root causes for unsuccessful outcomes for

safety or health technologies in the mining industry, which were identified in Chapter 5 and are

listed below :

Threat 1: Biases lead legislators to judge that immediate action is needed and to ignore


Threat 2: Biases lead regulators to judge that immediate action is needed and to ignore


Threat 3: Biases and political pressures lead researchers to ignore or to understate observed


166

Threat 4: Despite the best efforts of researchers and developers, effective interventions

either cannot be developed or cannot be demonstrated to be effective due to

engineering challenges or economic constraints

Threat 5: Biases lead to an acceptance of the status quo with respect to recognized

deficiencies in safety and health standards or technologies

Threat 6: Cultural forces and cognitive biases among miners lead to a mistrust of new

interventions

Threat 7: Biases result in insufficient or poorly designed experiments

Threat 8: Biases result in insufficient or ineffective review of research

It is important to note that the presence of these root causes is, for the most part, out of the

control of agencies involved in mining safety and health regulation or research. This is clearly

the case for some of the threats (for example, Threat 6). For most of the others, it is less clear

that the regulatory agencies, research agencies, and legislators cannot directly control these

threats. Most of the threats deal with cognitive biases on the part of individuals or groups within

these organizations, so a naïve view might be that these biases can be avoided through objective

thinking. However, biases are an unavoidable part of any human being’s thinking – it is a myth

to say that we can eliminate bias from our thinking. Moreover, these biases can be further

compounded by political forces and interactions within or between agencies. Rather, the key to

avoiding biases is to be vigilant for them in our own thinking as well as in the thinking of others

and to work to correct them when they occur. In organizations, this can be accomplished through

policies such as those for scientific peer-review and proper design of experiments. Since the

threats cannot be directly controlled or eliminated, it is necessary to implement policies which

167

are designed to prevent the presence of these threats from leading to the enactment of a law or

regulation that mandates the use of a safety or health technology that is immature.

In the event that a mandate is enacted for an immature technology, a number of undesirable

outcomes are possible. Examples of these were seen in Chapters 4 and 5 and fall into four

generalized categories:

Consequence 1: Intervention does not achieve the intended safety or health benefit

(An example is the lack of evidence that tracking systems provide a

material safety benefit)

Consequence 2: Intervention causes an unintended, negative safety or health consequence

(An example is the occurrence of electromagnetic interference between

the personal dust monitor and proximity detection systems)

Consequence 3: A device that fails to meet the safety and health standard or is otherwise

defective is certified and used

(An example is the continued certification and use of self-contained self-

rescuers with observed deficiencies)

Consequence 4: Despite effective interventions being available to meet the mandate, there

is sustained strong resistance to their use

(An example is the low adoption rate of noise controls for roof bolting

machines)

Figure 32 shows the threats and consequences for this bowtie analysis.

168

Figure 32: Threats contributing to the enactment of a law or regulation that mandates the use of a safety or health

technology that is immature

Threats Event

C2: Intervention causes an

unintended, negative health or

safety consequence

C4: Despite effective interventions

being available to meet the

mandate, there is sustained strong

resistance to their use

C3: A device that fails to meet the

health and safety standard or is

otherwise defective is certified and

used

C1: Intervention does not achieve

the intended health or safety

benefit

Consequences

Enactment of a

law or regulation

that mandates the

use of a health or

safety technology

that is immature

T1: Biases lead legislators to judge


and to ignore indications of

technology immaturity

T2: Biases lead regulators to judge



technological immaturity

T3: Biases lead researchers to

ignore or to understate observed

indications of technological

immaturity

T7: Biases result in insufficient or




T5: Biases lead to an acceptance of

the status quo with respect to

recognized deficiencies in safety

and health standards or

technologies

T4: Despite the best efforts of

researchers and developers,

effective interventions either

cannot be developed or cannot be

demonstrated to be effective due to

engineering challenges or

economic constraints

T6: Cultural forces and cognitive

biases among miners lead to a

mistrust of new interventions

169

6.2 Overview of Bowtie Analysis

With these threats and consequences in place, preventative controls can be developed to prevent

the enactment of immature technology mandates and recovery controls can be developed to

mitigate the enactment of such a mandate. A set of recommended controls is shown in Figure 33.

These controls were developed using the knowledge gained through the study of both successful

and unsuccessful safety and health technology outcomes in Chapters 4 and 5 and through

discussion with subject matter experts in the areas of safety and health technology development

and diffusion. Detailed discussion on how the controls shown in the figure is provided in this

chapter. These controls draw on tools such as Technology Readiness Levels (TRL) as discussed

in Chapter 2.

In the following sections, the controls associated with each threat and with each consequence

will be discussed, including a discussion of the rationale for the recommended controls and a

brief description of how these controls could be implemented at mining safety and health

regulatory and research agencies. In Chapter 7, a more detailed discussion of the

recommendations for these organizations is given.

170

Figure 33: Bowtie analysis of the enactment of a law or regulation that mandates the use of a safety or health technology that is immature

T1: Biases lead legislators to

judge that immediate action is

needed and to ignore

indications of technology

immaturity

T2: Biases lead regulators to

judge that immediate action is

needed and to ignore


immaturity


ignore or to understate

observed indications of


T7: Biases result in insufficient

or poorly designed experiments

T8: Biases result in insufficient

or ineffective review of

research

T5: Biases lead to an

acceptance of the status quo

with respect to recognized

deficiencies in safety and

health standards or

technologies




cannot be developed or cannot

be demonstrated to be effective

due to engineering challenges

or economic constraints

T6: Cultural forces and

cognitive biases among miners

lead to a mistrust of new

interventions

Threats Event Preventative Controls

PC2: Research and regulatory

agencies should implement

policies for the effective

communication of science-

based recommendations to

Congress and state legislatures

PC3: During the rulemaking

process, regulatory agencies

should conduct assessments of

technology readiness as part of

the normal technical and

economic feasibility

assessment



policies to perform technology

readiness assessments and to

publicly report these

assessments in a transparent

manner

PC6: Research agencies

should implement rigorous

policies for meaningful peer-

review of project proposals,

protocols, and publications



policies to seek engagement

with industry stakeholders

PC1: During legislative

process, assemble

congressional committees to

examine scientific evidence

and technological maturity



safety consequence

C4: Despite effective

interventions being available to

meet the mandate, there is

sustained strong resistance to

their use

C3: A device that fails to meet

the health and safety standard

or is otherwise defective is

certified and used

C1: Intervention does not

achieve the intended health or

safety benefit

Consequences Recovery Controls

RC4: Research and regulatory


policies to seek engagement

with industry stakeholders



policies to track technology

maturity development

RC1: Regulations should be

designed to allow for discretion

in enforcement

RC3: Agencies responsible for

safety and health product

certification should implement

policies to link product

certification to assessments of

technology maturity

Enactment of a law

or regulation that

mandates the use of

a health or safety

technology that is

immature

171

6.3 Discussion of Controls to Prevent the Enactment of a Mandate

for an Immature Safety or Health Technology

In this section, the left side (the threats and the associated preventative controls) of the bowtie

analysis given in Figure 33 will be discussed. This portion of the bowtie is shown in Figure 34.

In this section, each of the threats and associated preventative controls will be discussed in turn.

Figure 34: Left-hand side of bowtie analysis of the enactment of a law or regulation that mandates the use of a safety

or health technology that is immature, showing threats and preventative controls












immaturity









technologies











Threats Event Preventative Controls

PC2: Research and regulatory agencies

should implement policies for the

effective communication of science-based

recommendations to Congress and state

legislatures

PC3: During the rulemaking process,

conduct assessments of technology

readiness as part of the normal technical

and economic feasibility assessment


should implement policies to perform

technology readiness assessments and to

publicly report these assessments in a

transparent manner

PC6: Research agencies should

implement rigorous policies for

meaningful peer-review of project

proposals, protocols, and publications


should implement policies to seek

engagement with industry stakeholders

PC1: During legislative process,

assemble congressional committees to

examine scientific evidence and

technological maturity

Enactment of a

law or regulation

that mandates the

use of a health or

safety technology

that is immature

172

6.3.1: (T1) Biases lead legislators to judge that immediate action is needed and

to ignore indications of technology immaturity

The first threat (T1) is that biases may lead legislators to judge that immediate action is needed

and to ignore indications of technology immaturity. This was observed as one of the root causes

in the analyses of the unsuccessful outcomes associated with refuge alternatives and miner

tracking systems. The use of tracking technology was directly mandated by the MINER Act of

2006. The use of refuge alternatives was mandated by MSHA regulation, as directed by the

MINER Act. As was discussed in Section 4.1.1, the MINER Act was passed unusually rapidly

following the Sago Mine disaster and other disasters in 2006; the Sago disaster occurred in

January and by June, the Act had been signed into law. The public discourse following these

disasters, along with the unavoidable biases held by legislators as discussed in Sections 5.1.1 and

5.1.3, led legislators to judge that immediate action was needed to prevent similar disasters from

occurring in the future. With both technologies, there was a lack of evidence to show that the

technologies were mature and ready to be implemented through government mandate.

Nonetheless, these indications of immaturity were ignored.

It is impossible to eliminate the cognitive biases that contribute to legislative actions, such as the

passage of the MINER Act. Rather, the goal should be to prevent these biases from leading to

future mandates for immature safety and health technologies. Figure 35 shows the portion of the

bowtie analysis that is relevant to this threat and gives two possible preventative controls.

173

Figure 35: Partial bowtie analysis of the enactment of a law or regulation that mandates the use of a safety or health

technology that is immature, showing portion associated with Threat 1

The first of these (PC1) is a recommendation to Congress to, during the legislative process, to

assemble congressional committees to examine the scientific evidence relevant to the proposed

legislation and to critically assess the maturity of technologies that are proposed to be mandated.

This is perhaps the most open-ended and imprecise recommendation provided in this dissertation

– it will be up to the individual Senators and Representatives to decide how best to assess the

evidence for any proposed legislation, but a healthy degree of skepticism about new

interventions is advisable.

The second preventative control for this threat (PC2) has to do with how research and regulatory

agencies communicate with Congress about proposed or potential legislation. Specifically, these

agencies should provide science-based recommendations concerning existing as well as potential

new safety and health interventions. These recommendations should not be limited to positive

findings, but should also indicate when there is a lack of evidence and, therefore, a need for

further investigation. In other words, there should be an expectation that the maturity, efficacy,





Threat Event Preventative Controls


should implement policies for the

effective communication of science-based


legislatures

PC1: During legislative process,

assemble congressional committees to

examine scientific evidence and


Enactment of a

law or regulation

that mandates the

use of a health or

safety technology

that is immature

174

and suitability of a new intervention should be demonstrated before any mandate to use the

technology can be issued, and this expectation should be reflected in recommendations provided

by regulatory and research agencies to Congress.

In order for such recommendations to carry weight, it will be necessary for the agencies issuing

them to have an established track record of performing sound scientific research and also of

being authorities on the state of the art for emerging safety and health technologies. When one of

these organizations says that there is not sufficient evidence to support a proposed mandate, it

must be clear that, if such evidence existed, the organization would be aware of it. To make a

conclusive recommendation based on a lack of evidence, it must be possible to convincingly

dismiss the accusation “you just didn’t look hard enough.” The degree to which this accusation

can be convincingly dismissed is a function of how strongly the organization is perceived to be

an authority on emerging safety and health technologies.

To strengthen this perception, regulatory and research agencies should establish policies for the

continual (re)assessment of safety and health technologies in terms of their maturity and their

ability to address safety and health concerns. The use of tools such as technology readiness

assessments or product development lifecycle approaches could be used to do this. These

recommendations are discussed below for the second threat (T2).

175

6.3.2: (T2) Biases lead regulators to judge that immediate action is needed and

to ignore indications of technological immaturity

The second threat (T2) is that biases lead regulators to judge that immediate action is needed and

to ignore indications of technological immaturity. This is very similar to T1 in that those in

regulatory agencies are subject to the same unavoidable cognitive biases that cause flawed

thinking for legislators. These biases can lead to the enactment of regulations that mandate the

use of technologies that are immature, potentially leading to unsuccessful outcomes for these

technology mandates. This was seen in the root causes for the unsuccessful outcomes associated

with refuge alternatives and proximity detection systems, as discussed in Sections 5.1.1 and

5.1.4, respectively. In the case of refuge alternatives, the regulation was driven primarily by the

expectations established by the MINER Act, as was discussed above. For proximity detection

systems, the mandate for the use of this technology (as well as for the personal dust monitors that

were involved in the electromagnetic interference with proximity detection systems) was driven

by MSHA. However, in both cases, there was a lack of compelling evidence to conclude that the

technology was sufficiently mature and appropriate to be mandated.

As was discussed in the relevant sections of Chapter 5, the decision to proceed with regulations

mandating the use of refuge alternatives and proximity detection systems despite a lack

compelling evidence for their maturity can be traced back, in part, to biases on the part of

regulators. These biases are an unavoidable aspect of human thinking, so the focus should not be

on eliminating the biases, but rather on detecting them and preventing them from leading to the

enactment of mandates for immature technologies. The portion of the bowtie analysis which are

relevant to this threat is shown in Figure 36.

176



Two potential controls have been identified to prevent biases within regulatory agencies from

leading to the enactment of mandates for safety and health technologies that haven’t been

demonstrated to be mature. In contrast to T1, which had to do with biases among legislators and

is largely out of the control of mining safety and health organizations, this threat can be more

directly controlled through the implementation of policy changes within these organizations. The

two preventative controls identified (PC3 and PC4) are recommendations for such policy

changes.

The first (PC3) is the recommendation that during the rulemaking process, regulatory agencies

should conduct assessments of the technology’s readiness as part of the regular technical and

economic feasibility assessment, and the second (PC4) is that both research and regulatory

agencies should regularly perform technology readiness assessments. For any new regulation, a

determination of technical and economic feasibility must be made and must be supported by

documented evidence. As part of the research conducted to make this feasibility determination,

information on the readiness of any technology proposed to be mandated should be collected and







conduct assessments of technology

readiness as part of the normal technical






transparent manner

Enactment of a

law or regulation

that mandates the

use of a health or

safety technology

that is immature

177

analyzed. The question of feasibility is fundamentally different from the question of technology

maturity, but much of the same information can be used to answer both questions. Since a

significant effort is already expended on the determination of feasibility, it is wise to put in

somewhat more effort to concurrently investigate the readiness of the technology and to make a

complimentary determination of technology readiness. This technology readiness assessment

would be different from the normal feasibility investigation in that the processes and standards of

evidence would be clearly defined for the assignment of a given maturity level. In addition, the

use of a standardized evaluation framework would allow for clearer and more consistent

communication about the how the maturity determination was done and what evidence supports

the determination. Transparency in this process is critically important.

For this recommendation to be effective at mitigating the effects of biases in the regulatory

process, it is clearly necessary to conduct the analysis of technology readiness in a manner that

minimizes the influence of biases. This is accomplished by implementing processes for detecting

biases through objective reviews and established expectations for supporting evidence before

decisions are made. As was discussed in Section 2.4, the Technology Readiness Level (TRL)

scale provides a useful means of performing consistent evaluations of the maturity of

technologies with explicitly stated expectations for supporting evidence. The TRL scale was

developed by NASA [33, 34], and was adopted by the DOD in order to prevent the funding of

high-risk development efforts for emerging technologies with low levels of maturity [35]. The

DOD provides guidance in their Technology Readiness Assessment Deskbook on how the TRL

scale can be used in a structured way to manage the progression of technology research and

development efforts [36, 37].

178

Other tools, such as the Technology Readiness Level Calculator (TRLC) [41], the Technology

Program Management Model (TPMM) [42], and Technology Readiness Assessment guides [43,

37] have been developed by the DOD, DOE, and other organizations as ways of managing the

development of technologies through the TRL stages. In the private sector, many companies

employ similar methods to assess the maturity of their products and to manage the progression of

R&D efforts. The Product Development Lifecycle (PDLC) is a framework for managing all

aspects of product development and evaluation through all phases of technology maturity, from

conceptual stages through diffusion and marketing.

The PDLC framework is most applicable to situations where the entire product development is

under the direct control of the company or organization developing the technology. As such, it

has more limited applicability in situations where technologies are being developed through

more distributed means as would be the case for most safety and health technologies that would

be mandated for use in the mining industry. In other words, since the agencies mandating the use

of these technologies isn’t solely responsible for the decisions made during the technologies

development, the PDLC framework may not be entirely appropriate. However, lessons from this

approach can be useful nonetheless.

Namely, it is advisable to utilize a systematic approach to assessing and managing the

development of a technology even in the case that the development is not entirely under the

control of the organization conducting the assessment or driving the development. Under a

PDLC framework or under any of the frameworks for managing the funding of technology

development based on TRLs (e.g. the TPMM), decisions are managed in a structured way with

defined responsibilities for those involved in making the decisions and clear expectations for the

type of supporting evidence that is needed at each decision point. Suggestions on how such a

179

system might be implemented for mining safety and health research and regulatory agencies are

provided in Chapter 7.

Regardless of the details of how these tools might be used to manage key decisions in the

research and regulation of safety and health interventions, the use of tools based on TRL has

important advantages as were discussed in Chapter 2. The key advantages are that these tools

provide a common language with which the technology status can be clearly communicated, they

give a means of recognizing and managing risks associated with technology transition, and they

give a largely objective measure that can be used to make decisions concerning research funding,

acquisition, and most significantly here, regulation. NASA and DOD studies have quantified the

economic benefits of these tools [44, 45], and the analysis presented in Chapter 5 on the root

causes of unsuccessful outcomes for safety and health technology mandates shows the less

quantifiable risks associated with not using these tools.

6.3.3: (T3) Biases and political pressures lead researchers to ignore or to

understate observed indications of technological immaturity

The third threat (T3) is that biases amongst safety and health researchers in the mining

community may lead these researchers to ignore or understate observed indications of

technological immaturity. This was identified in the causal tree analyses for the unsuccessful

outcomes associated with refuge alternatives, SCSRs, and proximity detection, although it likely

plays a role in other cases as well. In the case of refuge alternatives, researchers saw in testing

that the chambers exhibited significant deficiencies, and, although these deficiencies were

publicly reported to Congress, the conclusions of this report stated that “the benefits of refuge

alternatives and the general specification of these alternatives are sufficiently known to merit

180

their commercialization and deployment in underground coal mines.” With SCSRs, researchers

repeatedly identified deficiencies with CSE SR100 SCSR units during LTFE testing that spanned

nearly two decades. Again, these deficiencies were publicly reported; however, the seriousness

of these deficiencies was either not recognized or was understated in the conclusions of these

reports, and the units continued to be certified and used. In the case of proximity detection,

researchers were told by mine operators that there were performance problems with proximity

detection systems that could potentially be attributed to electromagnetic interference, but these

claims were dismissed by the researchers and a rigorous study of EMI between personal dust

monitors and proximity detection systems was not conducted until after both technologies had

been mandated. Again, it is likely that the biases that contributed to these outcomes also played a

role in similar cases and these cases simply were not captured in this analysis due to a lack of

documented evidence.

The portion of the bowtie analysis associated with this threat is shown in Figure 37 and provides

one suggested preventative control (PC4), which is the same control as was discussed above for

T2, namely to implement policies within research agencies to perform technology readiness

assessments. In each of the three examples discussed for this threat, researchers made a

determination that the technologies were mature and ready for widespread use in the industry.

For refuge alternatives and SCSRs, this determination was explicit in recommendations to

Congress or in the continued certification of products for use. For proximity detection systems,

the determination was implicit in the lack of action to investigate reported performance issues.

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In all three cases, if a policy had been in place that established a structured framework for

determining the maturity of safety and health interventions with clearly defined expectations for

supporting evidence, it is unlikely that the research that had been conducted would have

supported a determination that the technologies were mature enough to merit a mandate for their

use. In Chapter 7, suggestions on how such a policy might be implemented are provided.

6.3.4: (T4) Despite the best efforts of researchers and developers, effective

interventions either cannot be developed or cannot be demonstrated to

be effective due to engineering challenges or economic constraints

The fourth threat (T4) is that despite their best efforts, it is sometimes not possible for

researchers and technology developers to develop and demonstrate an effective engineering

solution to a safety or health problem. This can be due to significant engineering challenges, as

was seen in the case of noise controls for roof bolters, or due to economic constraints, including

the constraint of limited resources to conduct research, as was seen in the case of tracking

systems.




immaturity

Threat Event Preventative Control





transparent manner

Enactment of a

law or regulation

that mandates the

use of a health or

safety technology

that is immature

182

As was discussed in Section 5.2.2, despite cooperative research and development efforts between

NIOSH researchers and equipment manufacturers, the drill chuck isolator, the drill bit enclosure,

and other noise controls for roof bolters were never successfully demonstrated to be effective

under operating conditions. As a result, these interventions were never listed as feasible in the

MSHA PIB and were never widely adopted by the industry. In a sense, this can be considered a

success of the mechanisms that were in place through the expectations established by MSHA

enforcement policies that a successful demonstration under operating conditions must first be

completed before an intervention could be considered to be feasible. It also showcases the harsh

reality that, despite well designed research and despite strong partnership between researchers

and product developers, it is still sometimes the case that an effective engineering solution will

simply not be found.

In contrast, the failure of researchers to produce compelling evidence that miner tracking systems

provide a material improvement to post-disaster safety can largely be attributed to a lack of

concerted research in this area. As was discussed in Section 5.1.3, although NIOSH had been

mandated by the MINER Act to conduct research on communications and tracking systems, the

bulk of that research was on communications and little was done on tracking. This was a

decision made under the economic and practical constraints of limited resources, facilities, and

personnel as well as in the presence of competing research focuses such as refuge alternatives

and proximity detection, for which regulatory mandates were concurrently being enacted. Again,

this highlights a harsh reality that, even when a safety or health problem is well appreciated, it

may be difficult to properly address the problem through research due to economic constraints.

In Figure 38, the portion of the bowtie analysis that is relevant to this threat is given and includes

one suggested preventative control, which again is PC4 as was discussed for the previous two

183

threats: Research and regulatory agencies should implement policies to perform technology

readiness assessments and to publicly report these assessments in a transparent manner. In this

case, it may be less clear how the use of these tools could prevent the enactment of a law or

regulation mandating the use of a technology that is immature. By assessing maturity in the early

stages of technology development as well as throughout the later stages, it will be possible to

better detect cases where there are indications that a technology is unlikely to be successful or

cases where there is a lack of sufficient evidence to conclude that the technology will be

successful. In addition, the information provided by these tools will help to make prioritization

decisions regarding the allocation of resources and the development of infrastructure or

expertise. By identifying which technologies represent lower risk development efforts, research

funding decisions can be based on an analysis of expected impact on safety and health issues. In

order to make this possible, it is necessary to continually assess the maturity of technologies that

are either being researched or that are being considered for research. Specific suggestions on

how a policy to use tools based on TRA or PDLC are given in Chapter 7.















transparent manner

Enactment of a

law or regulation

that mandates the

use of a health or

safety technology

that is immature

184

6.3.5: (T5) Biases lead to an acceptance of the status quo with respect to

recognized deficiencies in safety and health standards or technologies

The next threat (T5) is that biases can lead to an acceptance of the status quo with respect to

recognized deficiencies in safety and health technologies or standards. Examples of this are

discussed in the causal tree analyses for the unsuccessful outcomes associated with SCSRs and

proximity detection systems as discussed in Chapter 5.

With SCSRs, there were indications that the existing SCSR technologies were insufficient. In

particular, at disasters like Sago, miners had difficulty starting the units, had difficulty breathing

once the units were started, and had to remove the units in order to talk. Despite this, no action

has been taken to institute new standards for the design or functionality of SCSRs, due, at least in

part, to an acceptance of the status quo with respect to these apparent deficiencies.

The unsuccessful outcome analyzed for proximity detection systems, namely the occurrence of

EMI between the personal dust monitor and proximity detection systems, also shows a scenario

where the status quo was accepted with respect to existing safety and health standards or

technology. Standards designed to prevent EMI, including the allocation of the RF spectrum and

design standards for electromagnetic compatibility, do not apply to the underground mining

industry. This is certainly not because there has never been anyone in the mining community that

recognized the potential for EMI. This potential has long been understood, but this has not

resulted in action to implement changes to standards through regulation. Again, it is reasonable

to conclude that this is due, in part, to an acceptance of the status quo regarding the safety of

electronic devices in underground mines.

The portion of the bowtie analysis that is relevant to this threat is shown in Figure 39, and two

suggestions for preventative controls are given.

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The first (PC4) has already been discussed for the previous three threats and is to implement

policies to conduct assessments of technology readiness. By prompting the continual assessment

of the maturity of technologies in use in the mining industry, such policies would help to identify

deficiencies with existing standards or technologies earlier, and by explicitly stating clear

expectations for supporting evidence in order to justify a determination that a technology is

mature, these policies would force the discussion of the appropriateness and sufficiency of

existing standards. In addition, by assessing the readiness of technologies not yet in use in the

mining industry, opportunities might be identified for improvements to the status quo using

technologies or applicable standards from other industries. And a structured approach to the

decisions made using these assessments would again force the discussion of whether existing

changes are needed.

The second preventative control (P5) is that policies should be implemented within research and

regulatory agencies to seek engagement with industry stakeholders. Arguably, this is something

that the mining regulatory and research organizations already do well – seeking input from and





technologies






transparent manner




Enactment of a

law or regulation

that mandates the

use of a health or

safety technology

that is immature

186

engaging with the mining community. The small size of the industry makes it somewhat easier to

maintain this engagement. In addition, the high level of industry oversight (frequent and rigorous

government inspections and strict requirements for reportable incidents) give a strong incentive

for mine operators and other stakeholders to engage with the regulatory process. This incentive is

also strengthened by the unique nature of mining safety and health regulations, which are

focused on the limited jurisdiction of mining. Finally, the historical and ongoing influence of

labor organizations and lobbying groups in the mining industry create opportunities and

incentives for engagement and cooperation.

On the other hand, it could be argued that there are gaps in the level of engagement between

government agencies and the mining community, as demonstrated in cases that were analyzed in

this research. Regardless of whether current relationships between government agencies and

members of the mining community are strong or not, it is always worth further strengthening

those relationships. To do so, policies can be implemented that encourage, empower, and

incentivize employees of the agencies to more effectively engage with the stakeholders.

At a minimum, this would include making collaboration and partnering a priority in agency

strategic documents and communicating the importance of these values to employees. To enable

employees to fulfill this directive, competencies related to collaboration and partnering should be

developed. This can be done through training and other professional development activities.

Cascading personnel performance plan elements should be used to reinforce the importance of

these competencies and to put concrete plans in place for them. In addition to conventional

classroom training, other tools for developing these competencies can include mentoring,

coaching, and job shadowing.

187

Beyond training, policies to enable effective engagement with the industry can include the

organization of workshops, partnership meetings, webinars, and other opportunities for meetings

with as broad a cross-section of the mining community as possible. Meetings which bring

together researchers, regulatory representatives, mine operators, equipment manufacturers, labor

organizations, professional organizations, and other groups are critically important to the success

of efforts to foster engagement between the government and industry. There are several

requirements with which the organization of these meetings must comply, including those of the

Paperwork Reduction Act (PRA), which limits the administrative burden that the government

can place on the public, the Federal Advisory Committee Act (FACA), which governs the

formation and operation of advisory committees to direct the strategic planning of government

activities, and the Administrative Procedure Act (APA), which governs the process of

rulemaking. Within the constraints of these legal requirements, agencies should seek out and

create opportunities to bring the mining community together through meetings.

Finally, means of incentivizing industry engagement should be used. This can be accomplished

by writing goals related to engagement into employees’ performance plans and by rewarding

effective collaboration through performance awards and other means of formal recognition. In

addition to these formal means of formal recognition and incentives, creative ways of

incentivizing employees and to create a culture in which partnering is valued should be found.

Investment in fostering these relationships will pay dividends in that the safety and health needs

and opportunities in the industry will be better understood.

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6.3.6: (T6) Cultural forces and cognitive biases among miners lead to a


The next threat (T6) is related to T5 in that it could be addressed through better engagement with

the mining community. This is the threat that cultural forces and cognitive biases within the

community lead to a mistrust of new interventions. It should be no surprise that people are, to

varying degrees, resistant to change. There are significant barriers to the adoption of new

technology in the mining industry that contribute to this resistance to change, including barriers

to entry imposed by the small size of the industry and by regulatory standards such as

permissibility requirements. But it can also be attributed to an apparent culture of resistance to

and mistrust of new safety and health interventions. It should also be noted that this resistance

can be justified in many situations. Past situations, such as the cases studied in this research, in

which a new technology failed to achieve its intended safety or health benefit or created some

new hazard have occurred. These situation clearly give miners sufficient justification to be

skeptical of future interventions.

The portion of the bowtie analysis related to this threat is shown in Figure 40, and one

preventative control is given. This preventative control (PC5) has already been discussed above

and is to implement policies to improve engagement with the mining community. By doing so by

the methods described above, it will be possible to influence the mistrust many have in new

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interventions by earning trust and by ensuring that their needs are addressed.



6.3.7: (T7) Biases result in insufficient or poorly designed experiments and

(T8) Biases result in insufficient or ineffective review of research

The final two threats (T7 and T8) are closely related, are addressed by the same preventative

controls, and will be discussed here together. T7 is the threat that biases amongst researchers

lead to insufficient or poorly designed experiments, and T8 is the threat that biases amongst

those responsible for reviewing research will lead to insufficient or ineffective review. It should

be noted that sometimes it may be prohibitively difficult or even impossible to conduct properly

designed experiments due to a lack of needed cooperation. For example, if researchers do not

have access to a mine in which to conduct experiments, those experiments will not be conducted.

Similarly, it is possible that the vendor of a safety or health technology may seek to impede

research on their product by preventing researchers from obtaining the product to test.

These barriers aside, there are also cases in which researchers have access to the resources and

cooperation they need to conduct a proper experiment, but fail to do so. This was observed most

notably in the analyses of unsuccessful outcomes for SCSRs (Section 5.1.2) and for proximity

detection systems (Section 5.1.4). In the case of SCSRs, the testing conducted through the LTFE








Enactment of a

law or regulation

that mandates the

use of a health or

safety technology

that is immature

190

was insufficient to conclusively implicate quality control issues in the observed failures. As a

result, the results of the studies were left up to interpretation, and the conclusions were thus more

susceptible to being influenced by the cognitive biases of the researchers. Similarly, experiments

evaluating the performance of proximity detection systems failed to identify the possibility for

electromagnetic interference affecting the performance of the system. In this case, experiments

simply were not conducted to test for this possibility, which shows the biases of researchers who

decided that such experiments were not necessary.

The fault for these unsuccessful outcomes cannot be laid entirely at the feet of the researchers

directly responsible for conducting the experiments. Good science depends on proper peer-

review to overcome and counteract biases among researchers. At research organizations, policies

must be in place to ensure that research is being properly reviewed by appropriately qualified

and objective experts. Without well-defined policies for scientific review, these reviews are left

up to the judgement and discretion of the researchers and their management. Biases can

influence the decisions of either of these groups, leading to insufficient reviews. Thus, well-

defined and consistently-applied policies and procedures for review are needed. The

implementation of such policies is the last preventative control (PC6) recommended in this

dissertation and is shown in the relevant portions of the bowtie analysis in Figure 41 and Figure

42.

191





While peer-review is an integral part of any research process and policies for peer-review are

already in place at federal research agencies, there are opportunities to improve these policies. Of

critical importance to the effectiveness of peer-review is the independence of the review.

Whenever practical, blind reviews should be performed such that the researchers do not know

who is reviewing their work and the reviewers do not know whose work they are reviewing. This

helps to prevent conflicts of interest and subconscious biases from affecting the outcome of the








Enactment of a

law or regulation

that mandates the

use of a health or

safety technology

that is immature








Enactment of a

law or regulation

that mandates the

use of a health or

safety technology

that is immature

192

reviews. In addition, it is important to have oversight of the peer-review process incorporated

into the policy. It is necessary to assign responsibility to someone within the research agency to

check that reviewer comments have been appropriately addressed. Ideally, the person responsible

for this oversight task would be independent from the researchers’ normal chain of command,

but would be given the authority to halt research or dissemination activities that did not meet the

standards of scientific excellence and integrity.

There are several stages in the research process where oversight and review is important, and

there are several ways in which these stages can be delineated. For the purpose of this discussion,

a five-stage process for research is used, consisting of: (1) Project concept development, (2)

Project proposal and planning, (3) Design of experimental protocols, (4) Conduct of experiments

and analysis of results, and (5) Dissemination of results. This process is not necessarily a linear

progression through the stages. It is possible that the stages overlap and that the stages are re-

visited in an iterative process throughout the life of a research effort. At each stage, appropriate

and effect oversight and review is needed. This five-stage process, along with a brief statement

of the objective of review at each stage, is shown in Figure 43. This process is described for

intramural research (research conducted directly by the organization, as opposed to extramural

research, which is funded and overseen by the organization), but the expectations for effective

review in both intramural and extramural research should be consistent.

193

Figure 43: Five-stage process of research and reviews associated with each stage

Project concept development – At the earliest stage of a research effort, researchers will develop

a concept for a research project. The development of this concept should be informed by a

review of the research literature to identify research gaps as well as to identify opportunities

from innovation, an analysis of available injury and illness surveillance data to identify safety

and health needs, and engagement with mining stakeholders to understand the safety and health

challenges they face as well as the burden and impact that might result from the implementation

of a new intervention. At this stage, reviews should probe whether the project concept is justified

based on documented evidence of the need for the research, and the burden and impact that is

expected to be achieved through the successful completion of the research. These reviews can be

effectively conducted internally to the research organization – appropriate experts within the

Project concept development

Reviews should confirm that research concept is justified by a clear health or safety need, burden, and impact

Project proposal and planning

Reviews should confirm that the project plan is sound and that needed expertise, resources, and facilities are available

Design of experimental protocols

Reviews should confirm that experiments are designed in a scientifically valid and ethical way

Conduct of experiments and analysis of results

Reviews should confirm that established protocols are being followed and that adjustments to these protocols are valid

Dissemination of results

Reviews should confirm that publications, presentations, and other products present sound results and conclusions

194

organization should scrutinize the justification for the research project, and senior management

should make a decision on whether the concept should advance to the next stage.

Project proposal and planning – Once a determination has been made that a project concept is

justified, a project proposal must be written. This proposal should comprehensively document

the burden, need, and impact identified in the previous stage through literature review,

surveillance data analysis, and stakeholder engagement and should detail a plan of how the

research will be conducted, including descriptions of methods, analysis, and plans for

dissemination of results. The proposal should also state the availability of the expertise,

resources, equipment, and facilities needed to successfully complete the research.

For reviews, this is likely the most critical stage of the research process. The decision of whether

to commence a research project should be based on an objective assessment that the project is

likely to be successful, and that, if successful, the project is likely to address a safety or health

need. Reviews at this stage should include both internal and external peer-reviews. Experts from

outside the research organization should be sought out for their expertise for these reviews. To

the extent possible, the reviews should be conducted as blind reviews, with neither the reviewer

nor the researcher knowing who the other is. The number of reviews needed and the type of

expertise needed to conduct the reviews will vary, but procedures for these reviews should be

well documented and consistently applied to all project proposals.

Design of experimental protocols – Protocols for the conduct of experiments should, ideally, be

designed during the project proposal stage. However, due to the exploratory and adaptive nature

of research, it is often not possible at the outset of a research project to completely plan every

experiment that will be completed during the course of the project. Hence, protocols are often

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written throughout the course of a research project. These protocols can be for tests to be

conducted in laboratory settings or for tests to be conducted in the field at a cooperating mine

site. In either case, the protocol should thoroughly explain the motivation and justification for the

experiment as well as explaining methods to be used for data collection, data processing, data

analysis, data storage and sharing, and dissemination of results. In addition, protocols should also

discuss ethical considerations, including how the safety of researchers and, if applicable, human

subject will be protected. Protocols should also provide a review of relevant literature regarding

research methods and should utilize appropriate statistical and analytical methods to ensure that

supportable conclusions are reached.

The review of research protocols should be focused on ensuring the quality of the science and the

adherence to standards of scientific integrity. In the case of experiments involving human or

animal subjects, review by an Institutional Review Board (IRB) should be conducted to ensure

the protection of these subjects. Government research must also comply with laws limiting the

burden that can be placed on the public; for research involving surveys or interviews with

members of the public, this includes complying with the requirements of the PRA. Under the

PRA, government researchers must obtain approval from the Office of Management and Budget

(OMB) for any such study that collects information from ten (10) or more members of the

public. The processes for obtaining IRB and OMB approvals already represent effective

mechanisms for providing review of scientific research protocols.

Regardless of whether IRB or OMB approval is needed, research organizations should ensure

that appropriate peer-review of all research protocols is conducted. This can include both internal

and external review and should include reviews from individuals with all applicable areas of

expertise, including statistics and design of experiments, research ethics, and whatever technical

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area the protocol concerns. Procedures for obtaining protocol reviews should be consistently

applied to all research activities, and policies should be in place to prohibit the conduct of any

research activities not approved through the designated processes.

Conduct of experiments and analysis of results – If the review of the project concept has

confirmed the justification for the research, if the review of the project proposal has confirmed

the soundness of the research plan and the likelihood of successful, impactful results, and if the

review of research protocols has confirmed that experiments are being conducted using

scientifically and ethically appropriate methods, then minimal review of the actual conduct of the

research should be needed. However, oversight should be in place to ensure that projects proceed

according to the approved project proposal and that experiments are conducted according to

approved research protocols. Policies should be in place to monitor the progress of projects

through regular quarterly, semi-annual, or annual project reviews. The focus of these project

reviews should be to confirm that research is proceeding only according to approved plans.

Minor adjustments to the approved plans (for example, changes in personnel or timelines) are to

be expected, but if substantial adjustments to the approved plans are needed (for example,

fundamental changes to research methods or the addition of new major research tasks), the

appropriate stages of review should be re-visited – either a re-review of the project protocol or a

re-review of relevant research protocols.

Dissemination of results – Following the completion of an experiment or of a research project,

results and conclusions are typically disseminated through government-issued technical papers,

peer-reviewed journal articles, conference papers, and presentations. Research can also be

disseminated through less conventional means such as workshops, webinars, or software

applications. However research is disseminated, it is important that the products be sufficiently

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reviewed to ensure that they contain valid scientific methods, appropriate analysis, and

conclusions that are supported by the evidence.

For official government statements or documents, rigorous reviews are required, and in the case

of peer-reviewed journal articles, the journal will administer its own review process. However,

research organizations should not rely on these mechanisms to guarantee the quality of research

dissemination products. Consistently applied review practices should be used for all products.

Even for non-peer-reviewed products, such as conference papers or presentations, organizations

should, at a minimum, internally review the products prior to publication and should consider

whether a more rigorous external review is appropriate.

A final thought on the review of research is that, while established and consistently applied

processes for review are important, the culture of the organization with regard to review is also

important. Valuing peer-review should be part of the culture at a research organization, and

researchers should be encouraged to seek out review for their own research as well as to provide

review of others’ research. It is human nature to be uncomfortable with having our work

criticized or our objectivity questioned, but for science to have value, it must be backed by

rigorous and critical peer-review. It is challenging to overcome people’s resistance to criticism

and to get them to value critical review, but if a culture that values review can be created, the

validity and impact of the research will be strengthened. Efforts to instill this culture should be a

priority for any organization where research is conducted.

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6.4 Discussion of Controls to Mitigate the Enactment of a Mandate

for an Immature Safety or Health Technology

In the previous section, a number of preventative controls were suggested that could help to

prevent the enactment of a regulation or legislation mandating the use of a safety or health

technology that is immature, which represents the left half of the bowtie analysis given in Figure

33. In this section, the right half of the bowtie analysis will be discussed and a number of

recovery controls will be presented that could help to mitigate negative consequences associated

with the enactment of a law or regulation mandating the use of an immature safety or health

technology. The relevant portion of the bowtie analysis is shown in Figure 44.

Figure 44: Right-hand side of bowtie analysis of the enactment of a law or regulation that mandates the use of a

safety or health technology that is immature, showing consequences and recovery controls

On the left side of this figure is the event which corresponds with the middle of the bowtie: the

enactment of a law or regulation mandating an immature technology. On the right side of the

Event



safety consequence








used



benefit

Consequences

Enactment of a

law or regulation

that mandates the

use of a health or

safety technology

that is immature

Recovery Controls


agencies should implement policies

to seek engagement with industry

stakeholders



to track technology maturity

development


designed to allow for discretion in

enforcement





199

figure, are the negative consequences that can occur as a result of the enactment of such a

mandate. Whereas the threats used in the previous section were derived from the root causes for

unsuccessful outcomes of safety and health technology mandates obtained through the causal

tree analyses presented in Chapter 5, the consequences used in this section are generalizations of

the unsuccessful outcomes themselves. Between the event and the consequences on the bowtie

analysis are the recovery controls – strategies that can be used to help mitigate the impact of the

event and to decrease the likelihood that it will lead to the negative consequences.

In the following, each of the consequences will be discussed in turn, along with the associated

recovery controls.

6.4.1: (C1) Intervention does not achieve the intended safety or health benefit

The first negative consequence (C1) that could occur is that the mandated intervention might not

achieve the safety or health benefit that it is intended to achieve. Two examples in which this

might be the case are with refuge alternatives and tracking systems.

As was discussed in Section 5.1.1, at the time the RA regulation was passed and continuing to

today, there are many unanswered questions about the safety of RAs with regard to heat and

humidity buildup, the explosion resistance of components, the ingress of harmful gases, and

post-accident communications with the surface. Until a disaster occurs that necessitates their use,

it will be impossible to conclusively say whether the design of RAs is sufficient to protect the

lives of miners. However, the lingering questions with this technology merit concern.

200

Similarly, questions remain around whether tracking systems provide a material improvement to

safety during a post-disaster escape or rescue. While it is known that tracking systems provide a

level of functionality, there is not sufficient evidence to conclude that the use of these systems

will provide the information needed to substantially increase the likelihood of successful escape

or rescue following a disaster. As with RAs, the true safety value of these systems will not be

known until a disaster necessitates their use, but the questions are cause for concern.

The portion of the bowtie analysis that is relevant to this consequence is shown in Figure 45,

which suggests two recovery controls.


technology that is immature, showing portion associated with Consequence 1

The first recovery control (RC1) is that, where appropriate, regulations should be designed to

allow for discretion in enforcement. This recommendation is drawn from a lesson learned in the

causal tree analysis of the successful outcome for communications systems given in Section

5.1.3. With communications systems, MSHA recognized that the available systems could not

meet the letter of the MINER Act mandate for fully wireless communications between

underground and surface. The MINER Act contained a clause allowing for discretion in the

Event



benefit

Consequence

Enactment of a

law or regulation

that mandates the

use of a health or

safety technology

that is immature

Recovery Controls




development



enforcement

201

enforcement of this mandate by allowing for alternatives to a fully wireless system that

“approximate, as closely as possible, the degree of functional utility and safety protection

provided by the wireless two-way medium.” With communications systems, MSHA utilized this

discretion by issuing guidance on the use and enforcement of partially wireless communications

system. If appropriate, similar flexibility should be written into future regulations to permit the

enforcement of the regulation to be adaptable to the state of the technology.

As technology advances and as the nature of mining evolves, the enforcement of regulations

should adapt. To do this, it is necessary for regulatory requirements to allow for discretion and

flexibility on the part of the enforcement agency. It should be noted that this does not mean that

the discretion should be in the hands of individual investigators or individual district offices.

Rather, if a change in enforcement is needed and is permitted by the language of the regulation

or law, a policy change should be published and consistently enforced. With this flexibility, if a

situation occurs in which a mandated safety or health technology is suspected to be immature,

the enforcement of the mandate can be adjusted.

The second recovery control suggested (RC2) is that research and regulatory agencies should

implement policies to track technology maturity development for mandated, as well as emerging,

safety and health technologies. Presumably, by the time a technology is mandated, a

determination will have been made, either justifiably or not, that the technology is mature or that

it can be developed to maturity to satisfy the mandate. Once a rule is issued this question should

not be considered settled. Rather, the question of maturity should be revisited and tracked

throughout the development and diffusion of the technology.

202

For voluntarily-adopted technologies, adoption will follow an S-shaped curve as was discussed

in Chapter 2, with few early adopters, followed by a more rapid increase in adoption as others

see the benefits, and finally a slowdown in adoption as some of those who were resistant to the

new innovation gradually become late adopters. In the case of mandated technologies, adoption

rates are not organically determined in this manner; rather, adoption is driven by compliance

deadlines and enforcement, with even those who are resistant to the change being forced to adopt

the technology. This will result in more rapid adoption by a non-self-selecting user group, which

will provide a trial by fire for the technology under a wide variety of operating environments and

use conditions. As a result, the clearest picture of the technology’s readiness can often come

after the mandate for its use has been implemented.

For this reason, the period following the enactment and initial enforcement of a technology

mandate is a critical time to assess the success of the technology. As mine operators begin to use

the technology, they should be approached and encouraged to share their experiences and views.

Tests of the intervention’s performance under a wide variety of real operating conditions should

be conducted in as objective and quantifiable a manner possible, using appropriately designed

research protocols. The actual burden of the intervention’s use, both economically and

practically, on the mining industry should be assessed, both through the gathering of stakeholder

feedback and through objectively quantifiable means. All of this information should be utilized

in evaluating the maturity of the technology and in identifying areas where improvements are

needed. Tools based on TRL can be used for this, and a more detailed discussion on the use of

these tools is given in Chapter 7.

203

6.4.2: (C2) Intervention causes an unintended, negative safety or health

consequence

The second potential negative consequence (C2) of the enactment of a mandate for an immature

safety or health technology is that the deployment of the intervention may result in some

unintended negative impact on safety or health. An example of this was observed with the EMI

occurrence between personal dust monitors and proximity detection systems. Both devices

function correctly in that, under most circumstances, they achieve the intended safety or health

impact (i.e., reducing dust exposure and reducing the risk of striking/pinning accidents).

However, when the two devices are used together and are worn close to each other on a miner’s

belt, the unintended consequences of EMI occurs, effectively rendering the proximity detection

system inoperable. It is conceivable that, if a miner had come to expect the proximity detection

system to stop the motion of the machine when they got too close, that this could create a

scenario that is more hazardous than the situation without a proximity detection system installed

at all. This is one example of an unintended consequence of the introduction of a safety

intervention, but many other scenarios where the introduction of an intervention designed to

increase safety could, in fact, decrease safety in unexpected ways.

The relevant portion of the bowtie analysis related to this consequence, and the associated

recovery controls, is shown in Figure 46. The two recovery controls (RC1 and RC2) suggested

here for C2 are identical to those suggested for C1 in Figure 45. As with an intervention that fails

to deliver the intended safety or health benefit, the fallout from an intervention that delivers the

intended benefit but also creates some other unintended negative consequence could be mitigated

by allowing for discretion and adaptability in the enforcement of the mandate as well as by

continually tracking the maturity of the technology to identify and correct shortcomings.

204



6.4.3: (C3) A device that fails to meet the safety and health standard or is

otherwise defective is certified and used

The third type of negative consequence (C3) that could occur is that a device that fails to meet

the standards or intent of a safety or health mandate could be certified and used. This was

observed with the unsuccessful outcome associated with SCSRs, namely that an unacceptably

high rate of quality control failures occurred with a certified and widely used SCSR model.

Despite testing showing deficiencies with these units over nearly two decades, the model

continued to be certified and used. One could argue that this is not the result of a flawed

regulatory mandate, but rather the result of flawed certification procedures. Regardless, there are

lessons that can be learned to prevent similar situations from occurring in the future.

The relevant portion of the bowtie analysis is given in Figure 47. One recovery control (RC3) is

suggested: organizations responsible for certifying safety and health products for use in mining

should link the certification of these products to prior assessments of the maturity of the

underlying technologies. By doing so, it will more confidence will be able to be placed in the

correct functioning of the component technologies, and abnormal function, due to manufacturing

Event



safety consequence

Consequence

Enactment of a

law or regulation

that mandates the

use of a health or

safety technology

that is immature

Recovery Controls




development



enforcement

205

defect or other deficiencies will be more easily detected. In addition, the use of technology

maturity assessments will provide a framework under which rigorous scientific studies of the

capabilities of the technology will need to be evaluated as well as clear expectations for the type

and degree of supporting evidence needed to make a determination that a system is effective. A

discussion of how a policy requiring such assessments could be designed is given in Chapter 7.



6.4.4: (C4) Despite effective interventions being available to meet the mandate,

there is sustained strong resistance to their use

The last type of negative consequence (C4) that can result from the enactment of a mandate to

use a safety or health technology that is not mature is that the mining community may have

strong and sustained resistance the use of the mandated technology. This has been seen with

refuge alternatives, which many miners say they would not enter in the event of a disaster, and

noise controls for roof bolting machines, which have failed to achieve widespread adoption due,

in part, to the impact the use of these interventions has the normal operation of the machines. In

both cases, it can legitimately be argued that the underlying failure is that the interventions do

not provide the intended safety or health benefit (i.e., a consequence of type C1) and that

Event




used

Consequence

Enactment of a

law or regulation

that mandates the

use of a health or

safety technology

that is immature

Recovery Control





certification to assessments of

206

improving the performance of the technologies would alleviate the resistance to their use, but the

continued resistance to the use of the technologies is nonetheless a consequence worth

considering.

The relevant portion for this consequence is given in Figure 48, and one recovery control (RC4)

is suggested: research and regulatory agencies should implement policies to seek stronger

engagement with industry stakeholders.



This identically echoes a preventative control, PC5 (“Research and regulatory agencies should

implement policies to seek engagement with industry stakeholders”), which was suggested as a

way to address threat T6 (“Cultural forces and cognitive biases among miners lead to a mistrust

of new interventions”). The similarities between T6 and C4 should be apparent, but it is worth

noting that resistance to a new intervention will not go away simply because a regulatory or

legislative mandate has been issued for its use. This resistance is likely to continue, or even to

intensify, following the promulgation and enforcement of such a mandate. To overcome this

resistance, it is important to promote the value of collaboration and partnering, to develop

employees’ competencies for collaboration and partnering, to organize meetings with broad

Event





Consequence

Enactment of a

law or regulation

that mandates the

use of a health or

safety technology

that is immature

Recovery Control



to seek engagement with industry

stakeholders

207

cross-sections of the mining community, and to incentivize employees to engage with industry

stakeholders using performance plans and awards.

It may be difficult or even impossible to foster a cooperative relationship between government

and industry with respect to the enforcement of regulations. It would also be inappropriate to

build such a relationship to the point that the independence and objectivity of the regulatory

oversight could be called into question. Nevertheless, partnering and collaboration is critical to

success both before and after the passage of new rules.

208

Chapter 7: Guidelines and Recommendations to Improve

the Likelihood of Success for New Safety and Health

Technology Mandates

In the previous chapter, a bowtie analysis was presented in which the event at the center of the

bowtie was the enactment of a legislative or regulatory mandate to use a safety or health

technology that is not mature; the consequences at the right side of the bowtie were generalized

forms of observed unsuccessful outcomes resulting from immature safety and health

technologies that have been mandated; and the threats at the left side of the bowtie were

generalized forms of the root causes for those unsuccessful outcomes, which were informed by

the causal tree analyses presented in Chapter 5. Six preventative controls were formulated, which

will help to prevent the threats from leading to the event (the enactment of a mandate for an

immature intervention). In addition, four recovery controls, which will help to mitigate the

outcome of such an event and prevent or lessen the negative consequences were formulated.

In this section, a brief summary of these recommended preventative and recovery controls, most

of which call for policy changes at regulatory and research organizations, will be presented in

Section 7.1. Following this summary, since several of the recommendations deal with the use of

tools to assess and track the maturity of technologies, a discussion is provided in Section 7.2 on

how procedures to conduct such assessments might be designed.

7.1 Summary of Recommendations

The preventative and recovery controls identified through the bowtie analysis presented in

Chapter 6 are listed in Table 31.

209

Table 31: Summary of recommended preventative and recovery controls to prevent and mitigate, respectively, the

enactment of a legislative or regulatory mandate for the use of an immature safety or health technology

Preventative Controls Recovery Controls

PC1: During legislative process, responsible

Congressional committees should constitute

scientific panels to investigate technical issues

including the scientific evidence for


RC1: Regulations should be designed to

allow for discretion in enforcement


should implement policies for the effective

communication of science-based


legislatures

RC2: Research and regulatory agencies

should implement policies to track technology

maturity development


regulatory agencies should conduct

assessments of technology readiness as part of

the normal technical and economic feasibility

assessment

RC3: Agencies responsible for safety and

health product certification should implement

policies to link product certification to

assessments of technology maturity





transparent manner

RC4: Research and regulatory agencies






PC6: Research agencies should implement

rigorous policies for meaningful peer-review

of project proposals, protocols, and

publications

These controls would require policy changes in government agencies, with the exception of PC1,

which would require action by Congressional committees. The examples in this research were at

the federal level, but the conclusions apply at the state level as well. Recommendations PC2,

PC5, and RC4 deal with effective communication, including communication between

government agencies and Congress as well as communication between the same agencies and the

210

mining community. This communication is important for ensuring that regulations and

legislative recommendations from the agencies are based both on scientific evidence as well as

on the needs and opportunities in the industry.

Recommendation PC6 addresses scientific peer review, which is critical to the success of any

research program. Rigorous review of findings by qualified experts is necessary to ensure that

conclusions and policy are based on sound analysis of the data. Review is needed at all stages of

the research process, from the generation of a research concept through the dissemination of

results.

Most of the recommendations listed in Table 31 were discussed in Chapter 6, but four

recommendations that were not discussed in detail are PC3, PC4, RC2, and RC3, which address

the implementation of policies to assess and track technological maturity. Implementation of

such policies is examined in the next section.

7.2 Implementation of Policies to Assess Technology Maturity

Several threats identified as root causes for the unsuccessful outcomes analyzed in Chapter 5

could be, at least partially, controlled by having a consistently applied policy for the assessment

of technology maturity. Tools for assessing technology maturity and managing the advancement

of technologies through the levels of maturity would be valuable for enhancing the success of

safety and health technology development efforts for mining. One approach to assessing the

maturity of a technology was discussed in Chapter 2: Technology Readiness Levels (TRL).

TRL is a 9-level scale on which technologies and components can be more objectively evaluated,

as shown in Figure 49. TRL was developed by NASA in the 1980s [33, 34], and the system was

211

subsequently modified and adopted by several other organizations including the Department of

Defense [36, 37], the Department of Energy (DOE) [38], the European Space Agency [39], and

many others. It is recommended that some form of TRL should be used in mining to provide a

more consistent framework under which safety and health technologies can be evaluated and to

establish well-defined guidelines for the supporting evidence that should be expected in order to

make a determination that a technology is mature.

The wording of each of the nine technology readiness levels varies somewhat among agencies

utilizing the system, but the general idea behind each of the levels is consistent. The definitions

used by NASA and by DOD are shown in Table 32 along with a suggested set of definitions for

the mining industry. The first 5 levels are identical across these three scales, but there are minor

wording differences for TRL 6 through 9. For example, where the NASA scale refers to testing

in “a space environment,” the DOD scales refers to testing in “an operational environment,” and

the recommended mining scale refers to testing in “an operating mine.”

212

Figure 49: Technology Readiness Levels as defined by NASA [257]

213

Table 32: TRL definitions used by NASA and DOD as well as a suggested set of definitions for mining safety and

health technologies (These scales are identical for TRL 1 through 5 but have minor differences for TRL 6 through 9)

NASA Definition DOD Definition Suggested Mining Definition

TRL 9 Actual system 'flight proven'

through successful mission

operations

Actual system proven through

successful mission operations

Actual system proven through

successful use in active mining

operations under the range of

conditions expected to be

encountered in use

TRL 8

Actual system completed and

'flight qualified' through test

and demonstration (ground or

space)


qualified through test and

demonstration


demonstrated through field tests

TRL 7 System prototype demonstration

in a space environment

System prototype demonstration

in an operational environment

System prototype demonstration

in a representative operating

mine

TRL 6

System/subsystem model or

prototype demonstration in a

relevant environment (ground

or space)


prototype demonstration in a

relevant environment


prototype demonstrated in a


TRL 5 Component and/or breadboard

validation in relevant

environment

Component and/or breadboard


environment



environment

TRL 4 Component and/or breadboard

validation in laboratory

environment



environment



environment

TRL 3 Analytical and experimental

critical function and/or

characteristic proof of concept

Analytical and experimental

critical function and/or

characteristic proof of concept

Proof of concept established

through analytical or

experimental means

TRL 2 Technology concept and/or

application formulated

Technology concept and/or


Technology concept and/or


TRL 1 Basic principles observed and

reported

Basic principles observed and

reported

Basic principles observed and

reported

214

One important aspect of a TRL determination is the environment under which the technology has

been tested (e.g. laboratory environment, relevant environment, or operating environment) and

the actual environment under which the technology is expected to be used. For the mining

industry, the operating environment is clearly an operating mine, but this statement alone falls far

short of defining the environment. To best evaluate the readiness of the technology, the

following considerations should be taken into account:

• Mine characteristics, e.g. surface/underground, commodity, mining method, equipment

type

• Range of expected conditions under normal and abnormal operation, e.g. environmental

parameters

• Differences in operating conditions or practices at different mines

• Dependence on infrastructure (electrical power, water, GPS, data communication, etc.)

• Presence of other technologies in the environment (including the potential for EMI)

• Intended and unintended usage by miners

In many cases, a technology might have been successfully demonstrated or evaluated in a non-

mining environment and adapted to the mining environment. For example, node-based wireless

communications systems were successfully used in other industries before being adapted to use

in underground mines. Or a technology used in one mining environment might be adapted to

another mining environment.

Frequently, legislative or regulatory mandates are motivated by the notion that an existing

technology can be adapted to a mining application. A TRL determination for one operating

environment is not valid in another operating environment. However, having information on the

TRL in the prior environment can still be useful. Guidance on how a TRL for one operating

environment can be adjusted for another operating environment is shown in Table 33.

215

Table 33: Guidance for adjusting TRL for a technology that has been developed for and tested in some prior

environment and is being adapted to a new environment

Difference between new environment and prior environment

It is unknown

whether the

same basic

principles hold

in new

environment

Use in new

environment

represents a

fundamentally

different

application

Differences

environment

justify

laboratory

evaluation

Prior

environment

considered a

“relevant

environment”

for new

environment

New

environment is

practically the

same as the

prior

environment

TR

L i

n P

rio

r E

nv

iron

men

t

TRL 9

Actual system proven

through successful use

in active mining

operations under the

range of conditions

expected to be

encountered in use

↘TRL 0

Adjust TRL

in new

environment

to 0

↘TRL 2

Adjust TRL

in new

environment

to 2

↘TRL 4

Adjust TRL

in new

environment

to 4

↘TRL 6

Adjust TRL

in new

environment

to 6

↘TRL 8

Adjust TRL

in new

environment

to 8

TRL 8

Actual system

completed and

demonstrated through

field tests

TRL 7

System prototype

demonstration in a

representative operating

mine

TRL 6

System/subsystem

model or prototype

demonstrated in a


TRL 5

Component and/or

breadboard validation in


TRL 4

Component and/or


laboratory environment

No Change TRL in new environment is the

same as in the prior environment

TRL 3

Proof of concept

established through

analytical or

experimental means

TRL 2

Technology concept

and/or application

formulated

TRL 1

Basic principles

observed and reported

216

Assessments of the technology readiness of safety and health interventions can be performed at

any point during the intervention’s research, development, and diffusion. At each of these points,

the information provided by such an assessment would be beneficial for various reasons. Six

distinct scenarios in which having an assessment of the maturity of a health or a safety

technology would be useful have been considered:

1. The technology is under consideration by Congress to be mandated through legislation

2. The technology is under consideration by a regulatory agency to be mandated through

regulation

3. The technology is already mandated either through legislation or regulation

4. The technology is suspected to provide substantial safety or health benefits, but is not

widely adopted and is not under consideration to be mandated

5. The technology is widely and voluntarily adopted

6. The technology has been mandated and implementation has begun, but problems are

surfacing

This list is not meant to be exhaustive, but rather illustrative of the benefits provided by using

tools based on TRL. The effects of using such tools have been analyzed for four groups that

might conduct an assessment of technology readiness, use the results of an assessment of

technology readiness, or benefit from the use of such assessments:

1. Federal or state legislative bodies

2. Federal or state regulatory agencies, such as MSHA

3. Research agencies, such as NIOSH

4. The mining industry, including mine operators, equipment manufacturers, and others

217

Again, this is far from an exhaustive list, and might include, for example, universities, labor

organizations, and trade associations, among others. For each of the scenarios and

aforementioned groups, the effects on each the groups of using tools for assessing the readiness

of safety and health technologies has been considered. Tables 34 - 37 list some of the potential

benefits that could be received by Congress, regulatory agencies, research agencies, and the

mining industry, respectively.

For each of these tables, the effects of conducting an assessment of a technology’s readiness are

listed in three columns: (1) the effects that would be achieved if the assessment produces

definitive evidence that the technology is acceptably mature, (2) the effects that would be

achieved if the assessment produces definitive evidence that the technology is not acceptably

mature, and (3) the effects that would be achieved if the assessment is inconclusive.

There is no table to present the effects that would occur in terms of benefits to mineworkers, to

whom safety and health regulations and interventions are directed. Effectively, they will be the

primary beneficiaries of this process to ensure that mandated safety and health technologies are

able to accomplish their intended purpose and that ineffective technologies are not allowed to

consume resources, instill false confidence, or create unintended new hazards.

218

Table 34: Effects on federal and state legislative bodies of assessing the readiness of safety and health technologies

SCENARIO

EFFECTS ON CONGRESS OR STATE LEGISLATURES OF ASSESSING

TECHNOLOGY READINESS…

…if the assessment shows

that the technology is

acceptably mature

…if assessment shows that

the technology is not

acceptably mature

…if assessment is not

conclusive

TECHNOLOGY IS

UNDER

CONSIDERATION

BY CONGRESS TO

BE MANDATED

THROUGH

LEGISLATION

Legislation can proceed with

greater confidence that it will

achieve a positive safety or

health outcome

Legislation mandating an

immature technology can be

avoided

Legislation can be postponed

until sufficient evidence can be

found to make a conclusive

determination of maturity;

gaps in the evidence will be

identified, and specific

additional evidence can be

requested from government or

from industry

TECHNOLOGY IS

UNDER

CONSIDERATION

BY A

REGULATORY

AGENCY TO BE

MANDATED

THROUGH

REGULATION

Congressional oversight

committees will have greater

confidence that regulatory

agencies are developing

appropriate regulations


committees can identify

inappropriate actions by

regulatory agencies


committees can direct

regulatory agencies to provide

further justification for

regulatory actions or research

agencies to address knowledge

gaps

TECHNOLOGY IS

ALREADY

MANDATED

EITHER THROUGH

LEGISLATION OR

REGULATION

The success of prior legislation

mandating the technology will

be validated

Prior legislation mandating an


repealed or amended

Research agencies can be

directed and funded to address

the knowledge gaps needed to

make a conclusive


since the technology is already

mandated, this should be a top

priority

TECHNOLOGY

SHOWS THE

POTENTIAL TO

PROVIDE

SUBSTANTIAL

SAFETY OR

HEALTH

BENEFITS, BUT IS

NOT WIDELY

ADOPTED AND IS

NOT UNDER

CONSIDERATION

TO BE MANDATED

Potential legislation mandating

the use of the technology could

be considered

Legislation mandating an


avoided

If a legislative mandate seems

like a potential future

possibility, research agencies

can be directed and funded to

address knowledge gaps

TECHNOLOGY IS

WIDELY AND

VOLUNTARILY

ADOPTED

Will have greater confidence

that industry is working safely

Unintended consequences of

using an immature technology

can be identified; legislation

can be considered

If unintended consequences

are suspected possible,

agencies can be directed to


THE

TECHNOLOGY

HAS BEEN

MANDATED AND

IMPLEMENTATION

HAS BEGUN, BUT

PROBLEMS ARE

SURFACING

Results of the assessment can

be used to address problems as

they surface

Prior legislation mandating an


repealed or amended

Research agencies can be

directed and funded to address

the knowledge gaps needed to

make a conclusive




priority

219

Table 35: Effects on regulatory agencies of assessing the readiness of safety and health technologies

SCENARIO

EFFECTS ON FEDERAL OR STATE REGULATORY AGENCIES OF ASSESSING

TECHNOLOGY READINESS…



acceptably mature



acceptably mature


conclusive

TECHNOLOGY IS

UNDER

CONSIDERATION BY

CONGRESS TO BE

MANDATED THROUGH

LEGISLATION

Evidence supporting the

legislation can be provided to

Congress with confidence that

the mandate will be successful

A cogent recommendation that

the legislation should be

delayed or revised can be

provided to Congress and

supported by evidence

A recommendation can be

provided to Congress that

further research is needed,

including specific knowledge

gaps to address; the weight of

this recommendation will

depend on the agency’s track

record of effective technology

readiness evaluations and their

reputation as a technical

authority

TECHNOLOGY IS

UNDER

CONSIDERATION BY A

REGULATORY

AGENCY TO BE

MANDATED THROUGH

REGULATION

Regulation can proceed with

greater confidence that it will

achieve a positive safety or

health outcome

Regulation mandating an


avoided

Regulation can be postponed

until sufficient evidence is

found to make a conclusive


gaps in the evidence will be

identified, which can be shared

with research agencies to guide

strategy

TECHNOLOGY IS

ALREADY MANDATED

EITHER THROUGH

LEGISLATION OR

REGULATION

The success of prior

regulations mandating the

technology will be validated

Prior regulations mandating an


repealed or amended;

enforcement policy can be

adjusted to account for the

technology’s insufficiencies

Research can be conducted,

and assistance from research

agencies can be requested, to


needed to make a conclusive




priority

TECHNOLOGY IS

SUSPECTED TO

PROVIDE

SUBSTANTIAL SAFETY

OR HEALTH BENEFITS,

BUT IS NOT WIDELY

ADOPTED AND IS NOT

UNDER

CONSIDERATION TO

BE MANDATED

Potential regulation mandating

the use of the technology

could be considered

Regulations mandating an


avoided

If a regulatory mandate seems

like a potential future

possibility, research can be

conducted to address

knowledge gaps and efforts

can be coordinated with

research agencies

TECHNOLOGY IS

WIDELY AND

VOLUNTARILY

ADOPTED





can be identified; regulation

can be considered

If unintended consequences

are suspected possible,

research can be conducted to

address knowledge gaps and

efforts can be coordinated with

research agencies

TECHNOLOGY HAS

BEEN MANDATED AND

IMPLEMENTATION

HAS BEGUN, BUT

PROBLEMS ARE

SURFACING



they surface

Prior regulations mandating an


repealed or amended;


adjusted to account for the

technology’s insufficiencies

Research can be conducted,

and assistance from research

agencies can be requested, to


needed to make a conclusive




priority

220

Table 36: Effects on research agencies of assessing the readiness of safety and health technologies

SCENARIO

Effects on RESEARCH AGENCIES OF ASSESSING TECHNOLOGY READINESS…



acceptably mature



acceptably mature


conclusive

TECHNOLOGY IS

UNDER

CONSIDERATION

BY CONGRESS

TO BE

MANDATED

THROUGH

LEGISLATION


legislation can be provided to

Congress with confidence that

the mandate will be successful

A forceful recommendation

that the legislation should be

halted can be provided to

Congress and supported by

evidence


provided to Congress that

further research is needed,

including specific knowledge

gaps to address; the weight of

this recommendation will

depend on the agency’s track

record of effective technology

readiness evaluations and their

reputation as a technical

authority

TECHNOLOGY IS

UNDER

CONSIDERATION

BY A

REGULATORY

AGENCY TO BE

MANDATED

THROUGH

REGULATION


regulation can be provided to

the regulatory agency with

confidence that the mandate

will be successful

A cogent recommendation that

the regulation should be

delayed or revised can be

provided to the regulatory

agency and supported by

evidence


provided to the regulatory

agency that further research is

needed, including specific

knowledge gaps to address; the

weight of this recommendation

will depend on the agency’s

track record of effective

technology readiness

evaluations and their reputation

as a technical authority

TECHNOLOGY IS

ALREADY

MANDATED

EITHER

THROUGH

LEGISLATION OR

REGULATION

The effectiveness of safety and

health protections for miners

will be validated

Cogent recommendations for

needed changes to regulations

or legislation can be provided

to Congress and regulatory

agencies

Identifying knowledge gaps

will provide a clear strategic

direction; since the technology

is already mandated, this

should be a top priority

TECHNOLOGY IS

SUSPECTED TO

PROVIDE

SUBSTANTIAL

SAFETY OR

HEALTH

BENEFITS, BUT IS

NOT WIDELY

ADOPTED AND IS

NOT UNDER

CONSIDERATION

TO BE

MANDATED

Demonstrated maturity of the

technology will provide

evidence needed to promote the

use of the technology through

voluntary adoption or to

recommend regulatory action

Resources spent on research

into technologies with low

probability of success can be

minimized



direction and can be used to

strategically coordinate with

regulatory agencies

TECHNOLOGY IS

WIDELY AND

VOLUNTARILY

ADOPTED





can be identified and mitigation

strategies developed

If unintended consequences are

suspected possible, research

can be conducted to address

knowledge gaps and efforts can

be coordinated with regulatory

agencies

The technology has

been mandated and

implementation has

begun, but

problems are

surfacing



they surface

Cogent recommendations for

needed changes to regulations

or legislation can be provided

to Congress and regulatory

agencies



direction; since the technology

is already mandated, this

should be a top priority

221

Table 37: Effects on the mining industry of assessing the readiness of safety and health technologies

SCENARIO

EFFECTS ON THE MINING INDUSTRY OF ASSESSING TECHNOLOGY READINESS…



acceptably mature



acceptably mature


conclusive

TECHNOLOGY IS

UNDER

CONSIDERATION

BY CONGRESS

TO BE

MANDATED

THROUGH

LEGISLATION

Clearly defined performance

requirements for the

technology will be known,

enabling more effective

implementation

Objections to mandate for an



Government agencies can be

pressed to provide evidence of

technology’s maturity before a

mandate can be enacted

TECHNOLOGY IS

UNDER

CONSIDERATION

BY A

REGULATORY

AGENCY TO BE

MANDATED

THROUGH

REGULATION





implementation

Objections to mandate for an





technology’s maturity before a

mandate can be enacted

TECHNOLOGY IS

ALREADY

MANDATED

EITHER

THROUGH

LEGISLATION OR

REGULATION





implementation

Objections to mandate or

requests for changes to





technology’s maturity or to

change enforcement policy

TECHNOLOGY IS

SUSPECTED TO

PROVIDE

SUBSTANTIAL

SAFETY OR

HEALTH

BENEFITS, BUT IS

NOT WIDELY

ADOPTED AND IS

NOT UNDER

CONSIDERATION

TO BE

MANDATED

Proactive industry players can

lead the development and

implementation of promising

technologies in advance of any

legislative or regulatory

mandate

Investment in R&D efforts

unlikely to be successful can be

avoided; better

recommendations can be

provided to government

agencies

Knowledge gaps will be known

and can be used to guide R&D

efforts or to provide

recommendations to

government agencies

TECHNOLOGY IS

WIDELY AND

VOLUNTARILY

ADOPTED

The technology can be used

with greater confidence that it

will be effective


using an immature, even if

popular, technology can be

avoided

Knowledge gaps will be known

and can be used to guide R&D

efforts or to provide

recommendations to

government agencies

The technology has

been mandated and

implementation has

begun, but

problems are

surfacing





implementation

Objections to mandate or

requests for changes to





technology’s maturity or to

change enforcement policy

222

The question of what level of maturity qualifies as “acceptably” mature is not trivial. In these

scenarios in which a mandate requiring the use of the technology is being considered, the

acceptable level of maturity may be higher than in the acceptable level of maturity in other

scenarios. The question boils down to what an acceptable level of uncertainty is regarding the

ability of the technology to provide the desired safety or health benefit. This uncertainty can be

thought of as a function of the TRL; at lower TRLs, there is a high degree of uncertainty, and

this uncertainty decreases as the technology is proven and advanced through the TRLs. For

example, at TRL 2, the concept for the technology has been formulated, but there is no proof that

the concept is achievable. Obviously, this is substantial uncertainty.

By the time the technology reaches TRL 9, it will have been proven through successful use in

active mining operations, as well as having passed the prior TRL milestones, i.e. laboratory

evaluation, testing in a relevant environment. The uncertainty surrounding the performance

capabilities of the technology are not reduced to zero at this point, but they are significantly

reduced. It is still possible that, despite successful use in mines, changes in operating conditions

or practices, introduction of other technologies into the environment, system degradation, and

other factors may impact performance. If these changes are outside the range of conditions for

which testing has been conducted, it is unknown whether they will decrease efficacy.

Figure 50 shows some of the sources of uncertainty that are present at each TRL. To read the

figure for a given TRL, the horizontal band containing that TRL is extended to the right and all

vertical bands that it intersects are a remaining source of uncertainty at that TRL. So TRL 9 only

intersects one of the eight vertical bands, indicating the fewest sources of uncertainty, whereas

TRLs 1 and 2 intersect all eight vertical bands, indicating the most sources of uncertainty.

223

TRL 9 Actual system proven through successful use in active mining operations under the range of

conditions expected to be encountered in use

Ch

ang

es i

n o

per

atin

g c

on

dit

ion

s o

r p

ract

ices

, in

tro

du

ctio

n o

f o

ther

tec

hn

olo

gie

s in

to t

he

env

iro

nm

ent,

sy

stem

deg

rad

atio

n,

and

oth

er

fact

ors

may

im

pac

t p

erfo

rman

ce;

if o

uts

ide

the

ran

ge

of

cond

itio

ns

test

ed,

this

wil

l d

ecre

ase

effe

ctiv

e re

adin

ess

TRL 8 Actual system completed and demonstrated through field tests

Per

form

ance

may

dif

fer

un

der

co

nd

itio

ns

no

t in

clu

ded

in

tes

tin

g a

nd

dem

on

stra

tio

n;

Ch

ang

ing

con

dit

ion

s w

ith

in o

ne

min

e o

r d

isp

arat

e co

nd

itio

ns

bet

wee

n m

ines

may

lea

d t

o p

erfo

rman

ce d

iffe

ren

ces;

Un

exp

ecte

d u

se c

ases

m

ay o

ccur

un

der

op

erat

ing

con

dit

ion

s

TRL 7 System prototype demonstration in a representative operating mine

Cap

abil

itie

s o

f ac

tual

sy

stem

as

mas

s-p

rod

uce

d m

ay d

iffe

r fr

om

th

e ca

pab

ilit

ies

of

pro

toty

pes

TRL 6 System/subsystem model or prototype demonstrated in a


It i

s u

nk

no

wn

if

th

e re

lev

ant

env

iro

nm

ent

un

der

wh

ich

te

stin

g h

as b

een

co

nd

uct

ed

accu

rate

ly e

mu

late

s co

nd

itio

ns

at a

n o

per

atin

g m

ine TRL 5

Component and/or breadboard validation in relevant

environment

Key

co

mp

on

ents

of

the

tech

nolo

gy

hav

e no

t b

een

dem

on

stra

ted

to

wo

rk

un

der

min

ing

co

nd

itio

ns,

or

a co

mp

lete

pro

toty

pe

has

no

t b

een

ass

emb

led

TRL 4 Component and/or breadboard validation

in laboratory environment

Key

co

mp

on

ents

of

the

tech

nolo

gy

hav

e no

t b

een

dem

on

stra

ted

to w

ork

in

an

env

iro

nm

ent

oth

er t

han

a

lab

ora

tory

TRL 3 Proof of concept established

through analytical or

experimental means

Key

co

mp

on

ents

of

the

tech

nolo

gy

hav

e

no

t b

een d

emon

stra

ted

to

wo

rk i

n a

lab

ora

tory

en

vir

on

men

t

TRL 2 Technology concept

and/or application

formulated

Th

e co

nce

pt

of

the

tech

no

logy

is

no

t pro

ven

TRL 1 Basic principles

observed and

reported

Figure 50: Sources of uncertainty about technology's readiness at each TRL

224

So, as the technology is proven through laboratory testing, field testing, and finally successful

use in an operating environment, the uncertainty that the technology will provide the desired

benefit decreases, which means that the technology mandate under consideration is likely to be

successful. In Chapter 6, four general types of unsuccessful outcomes for safety and health

technology mandates were identified and are listed below:

Unsuccessful Outcome Type 1: Intervention does not achieve the intended safety or health

benefit

Unsuccessful Outcome Type 2: Intervention causes an unintended, negative safety or health

consequence

Unsuccessful Outcome Type 3: A device that fails to meet the safety and health standard or

is otherwise defective is certified and used

Unsuccessful Outcome Type 4: Despite effective interventions being available to meet the

mandate, there is sustained strong resistance to their use

As TRL increases, the risk that each of these unsuccessful outcomes will occur decreases.

However, these four risks do not all decrease at the same rate. Confidence that a Type 1 outcome

will not occur (i.e. confidence that the intervention will achieve its intended benefit) can

reasonably be said to begin increasing after successful proof-of-concept testing (TRL 3) and to

further decrease with laboratory and field testing (TRLs 4+). In contrast, confidence that a Type

2 outcome will not occur (i.e. confidence that unintended consequences such as EMI will not

occur) would not begin to increase until testing in a mine-like environment was conducted (TRLs

5+). Similarly, the risk of a Type 3 outcome cannot be said to be significantly reduce until the

capabilities of the technology’s components are proven and design specifications are established

(TRL 5+). Finally, a Type 4 outcome should be considered likely until the technology has been

demonstrated in a mine environment and successfully used by miners, i.e., that the technology

has achieved a TRL of 7 or greater. A visual representation of these decreasing risks for each of

the unsuccessful outcome types with increasing TRL is shown in Figure 51.

225

TRL 9

Actual system proven

through successful use in

active mining operations

under the range of

conditions expected to be

encountered in use

TRL 8

Actual system completed

and demonstrated

TRL 7

System prototype

demonstration in a

representative operating

mine

TRL 6

System/subsystem model

or prototype

demonstrated in a


TRL 5

Component and/or



TRL 4 Component and/or


laboratory environment

TRL 3

Proof of concept

established through

analytical or experimental

means

TRL 2 Technology concept

and/or application

formulated

TRL 1 Basic principles observed

and reported

Figure 51: Risk of unsuccessful outcomes decreases with increasing TRL; relative level of risk for each type of

unsuccessful outcome is indicated by the width of the column, which decreases with increasing TRL

Risk of

unsuccessful

outcome type 1:

Intervention

does not

achieve the

intended health

or safety benefit

Risk of

unsuccessful

outcome type 2:

Intervention

causes an

unintended,

negative health

or safety

consequence

Risk of

unsuccessful

outcome type 3:

A device that

fails to meet the

health and

safety standard

or is otherwise

defective is

certified and

used

Risk of

unsuccessful

outcome type 4:

Despite

effective

interventions

being available

to meet the

mandate, there

is sustained

strong

resistance to

their use

226

Based on the uncertainty presented in Figure 50 and the risks of an unsuccessful technology

mandate outcome presented in Figure 51, an informed decision can be made regarding what

might be an appropriate TRL to require before a technology mandate can be considered. For a

TRL of 6 or below, there is still significant uncertainty since a complete prototype has not yet

been demonstrated at an operating mine. As a result, the risk of all four types of unsuccessful

outcomes would be substantial. To reach a TRL of 8, a manufactured product (as opposed to a

prototype) must be demonstrated in an operating mine. For a technology-forcing mandate, i.e., a

mandate specifically designed to be promulgated before a product is on the market, it would not

make sense to require TRL 8 to be achieved.

Therefore, TRL 7 is a reasonable threshold level to set as what must be achieved before a

technology can be considered mature enough for a mandate to be appropriate. At this TRL, a

prototype of the technology has been tested and demonstrated in an operating mine. Even at this

stage of maturity, there is a degree of uncertainty concerning the capabilities of the technology.

As is shown in Figure 50, the sources of this uncertainty include the following:

• Capabilities of actual system as mass-produced may differ from the capabilities of

prototypes.

• Changing conditions within one mine or disparate conditions between mines may lead to

performance differences.

• Unexpected use cases may occur under operating conditions.

• Evolving operating conditions or practices, introduction of other technologies into the

environment, system degradation, and other factors may impact performance.

227

With these uncertainties, it is possible that the mandate may result in an unsuccessful outcome of

the types shown in Figure 51. In order to minimize these risks, it is necessary to minimize the

uncertainties of the types listed above. Consideration of these uncertainties should be built into

the determination of TRL. In particular, an assignment of TRL 7 to a prototype technology

should account for the following considerations:

• There should be evidence that the capabilities of the prototype are representative of what

would be achievable with the manufactured product. To do this, the manufacturing

capabilities in the industry should be well understood and channels for technology

diffusion should be established through engagement and partnering. Recommendations in

this area were previously discussed as PC5 (“Research and regulatory agencies should

implement policies to seek engagement with industry stakeholders”).

• The certification of products as meeting the requirements of the mandate should be tied to

clearly-defined technical capabilities, which will be produced through the assessment of

the maturity of the technology. This was previously discussed as RC3 (“Agencies

responsible for safety and health product certification should implement policies to link

product certification to assessments of technology maturity”).

• Testing in the field and in the lab should be designed to capture, to the extent feasible, the

full range of operating conditions under which the technology could be used. For

example, for underground mining interventions, testing should be conducted in mines of

various seam heights and geologies. This should also include testing for the potential for

electromagnetic interference and other environmental factors that could impact

performance. This is closely tied to PC6 (“Research agencies should implement rigorous

policies for meaningful peer-review of project proposals, protocols, and publications”).

228

• As the technology is introduced, the manner in which the industry is actually using the

technology and the issues that are occurring should be tracked by active engagement with

stakeholders. This was discussed as RC4 (“Research and regulatory agencies should

implement policies to seek engagement with industry stakeholders”).

• Finally, the presence of uncertainty in the capabilities of the technology should be

recognized and accounted for by designing regulations to allow for discretion and

flexibility to adjust to evolving industry conditions and advances in technology. This was

discussed as RC1 (“Regulations should be designed to allow for discretion in

enforcement”).

If the above considerations and recommendations are built into the determination of technology

readiness for a new intervention and if the technology can, subject to those considerations, be

successfully demonstrated to meet a TRL of 7, a much higher degree of confidence can be placed

on the expected success of the technology’s introduction. These guidelines should be used in the

processes for proposing new regulations as well as for formulating recommendations by research

agencies to regulatory agencies as well as recommendations from both types of agencies to

Congress and state legislatures.

229

Chapter 8: Conclusions and Recommendations

This dissertation set out to identify the factors that govern the success of mandated safety and

health technologies in the mining industry and to develop a set of guidelines that can be used to

maximize the likelihood of success for future mining safety and health technology mandates.

This goal was accomplished by analyzing several cases of safety and health technology

introduction to the industry. These case studies included technologies that were mandated

through legislation or regulation as well as technologies that were voluntarily adopted by the

mining industry. The root causes for the success or failure in each of these case studies were

determined and these root causes were analyzed to identify factors that were key to the success

or failure of the introduced technologies

For each case, the factual basis for the analysis came from the research literature and government

records, as well as through discussions with subject matter experts. Successful outcomes

clustered into four categories: (1) Wide-spread voluntary adoption; (2) Documented successful

trials; (3) Documented evidence of an achieved safety and health benefit; and (4) Indication of

broad applicability throughout the industry. Unsuccessful outcomes clustered into six categories:

(1) Documented failures of the technology; (2) Introduction of a new hazard due to the

technology’s use; (3) Low levels of adoption despite demonstrated ability to meet regulatory

standards; (4) Judicial intervention in rule-making or enforcement; (5) Strong resistance to the

deployment and use of the technology by miners; and (6) After-rule time extensions.

Within the cases analyzed, three successful and six unsuccessful outcomes were identified falling

into these categories. A causal tree analysis was performed for each of these successful and

unsuccessful outcomes to find the root causes that resulted in either success or failure. The root

230

causes from these analyses were compared and formulated into a set of generalized root causes

for successful outcomes and another set for unsuccessful outcomes.

Ten generalized root causes for successful outcomes, shown in Table 38, and eight generalized

root causes for unsuccessful outcomes, shown in Table 39, were identified. An examination of

these root causes revealed four interesting themes.

• The accurate assessment of technology readiness contributes to success. Three of the

generalized root causes for unsuccessful outcomes (items 1 through 3 in Table 39)

involve biases among researchers, regulators, or legislators leading to a failure to

accurately assess the readiness of a safety or health technology. In contrast, five of the

generalized root causes for successful outcomes (items 1 through 5 in Table 38)

involve researchers, regulators, or legislators correctly assessing technology

readiness.

• Research based on sound scientific methods and study design contributes to success.

Two of the generalized root causes for unsuccessful outcomes (items 4 and 5 in Table

39) involve poorly designed experiments or ineffective review of research. In

contrast, two of the generalized root causes for successful outcomes (items 8 and 9 in

Table 38) involve the successful completion of well-designed scientific research.

• Effective engineering solutions can be developed through partnerships between

stakeholders. Three of the root causes for unsuccessful outcomes (items 6 through 8

in Table 39) describe failures to develop effective interventions that address the needs

of the industry and that are accepted by miners. In contrast, two of the root causes for

successful outcomes (items 7 and 10 in Table 38) describe partnerships between

231

researchers and stakeholders to develop effective engineering solutions that address

the needs of the industry.

• The practice of incorporating provisions into regulations that will allow for

technology development is beneficial, and this is reflected in two of the successful

outcome root causes (items 5 and 6 in Table 38).

The identification of the root causes for successful and unsuccessful safety and health technology

introduction outcomes represents the first major contribution of this research. The identification

of the root causes fills a critical knowledge gap in the understanding of the challenges and

opportunities faced during the introduction of new safety and health technologies to the mining

industry. This research has shown how the factors identified resulted in the successful and

unsuccessful outcomes observed in the case studies. A high degree of consistency was observed

in the root causes identified across the analyses for all of the unsuccessful outcomes. This

consistency indicates that these findings are generalizable to other technology introductions and

that the findings can be used to inform future efforts to introduce new safety and health

technologies.

232

Table 38: Generalized forms of identified root causes for successful outcomes in case studies of safety and health

technology introductions studied

Generalized Root Causes for Successful Safety and Health Technology Introduction

Outcomes

11. Legislators correctly identified an opportunity for a technology-forcing mandate to

result in the development of new, or adaptation of, existing technologies.

12. Legislators correctly identified the need for research and development to achieve

successful results for a technology-forcing mandate.

13. Legislators correctly identified uncertainty in the ability of industry to meet the

provisions of a technology-forcing mandate and permitted flexibility in compliance to

allow for technology development.

14. Regulators correctly identified indications of technological immaturity.

15. Regulators correctly identified the need for flexibility in regulations to allow for

technology development.

16. Regulatory requirements were written as performance-based standards

17. Researchers established effective partnerships with industry in order to develop

research findings into practical interventions that can be effectively diffused.

18. Research agencies correctly identified need for specific research and acted to fulfill the

need.

19. The effectiveness of intervention was successfully demonstrated in field trials under

operating conditions.

20. The interventions were designed such that they had minimal impact on mine operations

and/or offered an additional benefit beyond the intended safety or health benefit.

233

Table 39: Generalized forms of identified root causes for unsuccessful outcomes in case studies of safety and health

technology introductions studied

Generalized Root Causes for Unsuccessful Safety and Health Technology Introduction

Outcomes

9. Biases led legislators to judge that immediate action is needed and to ignore indications


10. Biases led regulators to judge that immediate action is needed and to ignore indications


11. Biases led researchers to ignore or to understate observed indications of technological

immaturity identified through research

12. Biases resulted in insufficient or poorly designed experiments

13. Biases resulted in insufficient or ineffective review of research

14. Biases led to an acceptance of the status quo with respect to recognized deficiencies in

safety and health standards or technologies

15. Despite the best efforts of researchers and developers, effective interventions either

could not be developed or could not be demonstrated to be effective due to engineering

challenges or economic constraints

16. Cultural forces and cognitive biases among miners led to a mistrust of new

interventions

In addition, a high degree of consistency was observed across the root causes for the successful

outcomes, and these root causes showed a logical contrast to the root causes for the unsuccessful

outcomes. The contrast between the root causes for the unsuccessful and successful outcomes are

observed across four major themes: (1) the accurate assessment of technology readiness

contributes to success, (2) the completion of research based on sound scientific methods and

234

study design contributes to success, (3) effective engineering solutions can be developed through

partnerships between stakeholders, and (4) having regulations that allow for technology

development is beneficial. The contrast between the identified causes for successful and

unsuccessful outcomes with respect to these four themes is to be expected if these causes have

predictive value for the success of new safety and health technology introductions. The fact that

the expected contrast is observed validates that the factors identified do have predictive value

and that they can be used to inform guidance for the introduction of future safety and health

technologies.

To develop such guidance, a bowtie analysis for unsuccessful mining safety and health

technology mandates was constructed using the results of the causal tree analyses. At the center

of the bowtie analysis was placed the event, “Enactment of a law or regulation that mandates the

use of a safety and health technology that is immature.” On the left side of the bowtie analysis

were the threats, which are the eight generalized root causes for unsuccessful outcomes, and on

the right side of the bowtie are the consequences, which are generalized forms of the

unsuccessful outcomes themselves. This bowtie was used to identify preventative controls,

which are designed to prevent the threats from leading to the event, and recovery controls, which

are designed to mitigate the effects of the event. Six preventative and four recovery controls were

identified, which are listed below.

Preventative Control 1: During legislative process, responsible Congressional committees

should constitute scientific panels to investigate technical issues

including the scientific evidence for technological maturity

235

Preventative Control 2: Research and regulatory agencies should implement policies for

the effective communication of science-based recommendations to

Congress and state legislatures

Preventative Control 3: During the rulemaking process, regulatory agencies should conduct

assessments of technology readiness as part of the normal technical


Preventative Control 4: Research and regulatory agencies should implement policies to

perform technology readiness assessments and to publicly report

these assessments in a transparent manner

Preventative Control 5: Research and regulatory agencies should implement policies to

seek engagement with industry stakeholders

Preventative Control 6: Research agencies should implement rigorous policies for

meaningful peer-review of project proposals, protocols, and

publications

Recovery Control 1: Regulations should be designed to allow for discretion in

enforcement

Recovery Control 2: Research and regulatory agencies should implement policies to

track technology maturity development

Recovery Control 3: Agencies responsible for safety and health product certification

should implement policies to link product certification to

assessments of technology maturity

Recovery Control 4: Research and regulatory agencies should implement policies to

seek engagement with industry stakeholders

236

The development of these controls represents the second major contribution of this research. A

detailed discussion on recommendations for how these controls could be implemented for the

mining industry was presented in the previous two chapters. While the bowtie analysis was not

designed explicitly to do so, it is worth noting that the controls developed through this analysis

address the four themes previously discussed with the causal tree analysis results. These themes

again are: (1) the accurate assessment of technology readiness contributes to success, (2) the

completion of research based on sound scientific methods and study design contributes to

success, (3) effective engineering solutions can be developed through partnerships between

stakeholders, and (4) having regulations that allow for technology development is beneficial. The

first theme is addressed by Preventative Controls 1, 3, and 4 as well as by Recovery Controls 2

and 3. The second theme is addressed by Preventative Controls 2 and 6. The third theme is

addressed by Preventative Control 4 and Recovery Control 4. And the fourth theme is addressed

by Recovery Control 1.

The primary purpose of several of these controls is to maintain objectivity in the decisions that

are made in the planning of research, the design of new safety and health legislation or

regulation, and the enforcement of existing legislation and regulations. The importance of

maintaining objectivity in these processes cannot be understated. As has been discussed

extensively, biases affecting the thinking of those involved in making these decisions can lead to

many undesirable outcomes. Means of maintaining objectivity represented in the recommended

controls include performing technology readiness assessments and conducting research

according to rigorous, peer-reviewed scientific processes. The flawed thinking and biases that

affect the decisions made by researchers, regulators, and legislators should be considered an

unavoidable fact of life. Therefore, it is necessary to have strictly defined standards for evidence

237

to support decisions regarding regulation, legislation, or research. These standards should be

implemented in as consistent and transparent a manner possible.

Recommendations for such standards have been provided in the preceding chapters, most

notably including the recommendation to conduct systematic assessments of technology maturity

using Technology Readiness Levels (TRLs). When coupled with other controls recommended,

including the use of proper scientific experimental design, development of strong engagement

between government agencies and industry stakeholders, and policies for effective science-based

communication, the use of TRL assessments will ensure the objectivity of decisions concerning

whether a technology is mature enough to be mandated as well as to guide research and

development strategy. A mining-specific TRL scale definition was developed, and is shown in

Error! Reference source not found..

The expected effects of utilizing a scale of this sort for performing consistent technology

readiness assessments were described in the previous chapter and include providing for more

cogent recommendations concerning proposed regulations or legislation, offering a means of

identifying research gaps and guiding research strategy, and establishing clearly communicated

and consistently applied expectations for the maturity of technologies to be mandated or used in

the industry.

238

Figure 52: Recommended TRL definitions for mining safety and health technologies

239

The findings of this research fill a critical knowledge gap on the understanding of the factors that

influence the success of new safety and health technology introduction in the mining industry.

This new knowledge has been used to develop recommendations for future safety and health

technology introductions. By using the findings of this research and by applying the

recommendations provided in this dissertation, more impactful safety and health research can be

planned and performed and more effective safety and health regulations can be designed for the

mining industry.

240

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Vita

Jacob L. Carr

Education

PhD in Energy and Mineral Engineering: The Pennsylvania State University

Dissertation Title: “An Investigation into the Factors That Govern Success for New

Safety and Health Technologies in the Mining Industry and the Efficacy of those Factors

to Predict the Likelihood of Success for Emerging Technologies”

M.S. in Mining Engineering: University of Nevada, Reno

December, 2008; Thesis Title: “Application of Computer-Assisted Control Architecture

to the Operation of Large Surface Mining Shovels and Excavators”

B.S. in Mining Engineering: University of Nevada, Reno

December, 2006

Research Experience

Team Leader for the Machine Safety Team at NIOSH’s Pittsburgh Mining Research Division

2015 – Present

Safety Engineer at NIOSH’s Pittsburgh Mining Research Division

2009 – 2014

Graduate Research Assistant at the University of Nevada, Reno

2007 – 2008

Undergraduate Research Assistant at the University of Nevada, Reno

2004 – 2006

Professional Membership

Member of Society of Mining, Metallurgy, and Exploration (SME) since 2002

Honors and Awards

JW Woomer Young Engineer Award, 2018

University of Nevada, Reno, College of Science: Young Alumnus of the Year, 2017

Presidential Early Career Award for Scientists and Engineers (PECASE), 2016

Stefanko Best Paper Award, 2013

CDC & ATSDR Honor Award – Excellence in Leadership, 2013

Pittsburgh FEB Outstanding Professional Employee in a Medical/Scientific Field, 2012

University of Nevada, Reno: Outstanding B.S. Student, Mining Engineering, 2006

Publications

Author or co-author on more than 30 research publications, including conference papers, journal

articles, and book chapters on mining equipment automation, proximity detection systems, mine

illumination, RF and magnetic field propagation and modeling, and electromagnetic interference

mitigation.

an investigation into the factors that govern …

Documents