process and plant safety hazards
TRANSCRIPT
Process and Plant Safety Hazards
Ching, Warren
Cu, Joshua
Javier, Mike
So, Jonathan
Uy, Jeckson
Introduction
Process and Plant Safety Hazards
Process and Plant Safety Hazards Involves the application of scientific,
engineering, and management principles.
Aimed in the identification, characterization and contol of process and plant hazards.
To prevent injuries and incidents that can cause harm to employees or the public.
Professional Organizations Involved American Society of Safety Engineers. National Safety Council.
What do they do?
These professional organization consider the safety, health and welfare of workers and the public.
Whenever safety, health and welfare are in question.
They have an obligation to advise employers or appropriate authorities
Center for Chemical Process Safety (CCPS) By the American Institute of Chemical
Engineers Established in 1985 Develop and disseminate technical
information. Prevention of major chemical accidents.
Chemical safety management
FYI: Chemical industry has fairly low accident rate compared to other industry.
Risk can be further reduce to protect employees and general public.
Requires integrated approach.
Table 10-1 An integrated approach… Goals and Objectives of the safety program Risk Analysis and Management Industrial process design and operation Mechanical integrity of process equipment Safety Regulations, Codes and Standards Project Safety and Health Review Hazard Evaluation of process design and operation Personnel Motivation and Training Process and Plant Modification and Change Incident Investigation and Safety audits
Goals and Objectives of the Safety Program.Most Important Goal of Process and Plant
Design Safe Development Design Construction Start-up Operation of the plant
Examples of Major Industrial Accidents Occurred with Union Carbide in Bhopal, India
December 3, 1984 , methyl isocyanate (MIC) gas leaked. Philips Petroleum Company in Houston, Texas
On Oct. 23, 1989, about 40 tons of flammable vapor were accidentally released and ignited.
ARCO in Channelview, Texas A deadly blast ripped through the Channelview, Texas
ARCO Chemical Co. plant on July 5, 1990, killing 17 non-unionized workers and transforming a 564 acre petrochemical complex into a heap of mangled, charred metal.
Safety Risk Reduced to Lowest Practical Level Through a clear understanding of the:
Process Design Operation Mechanical Integrity of Equipment
For the EMPLOYERS
Made aware of : Safety Regulations Codes Standards
This should never be knowingly violated
in the design
and operation of the facility.
Management of projects
Should include a safety and health review.
Hazard evaluation of process and plant design.
Adequate training to personnel involved in development, design, construction and operation of the facility.
Management of projects
Proper motivation for the personnel mentioned in order to accomplish safety goals of the safety program.
Reassessment of all process and plant modifications, future changes in design and operation of the facility.
Management of projects
Any incident involving the process or plant should cause immediate concern and result in thorough, objective critique and investigation to determine the cause of the incident.
Near miss accident should also be investigated to determine cause.
Periodical safety audit by experienced, qualified team.
Management of projects
Dedicate sufficient resources to reduce risk of hazards. Personnel Equipment Time Money
Benefits of Safety
Adds to capital expenditures required and the operating costs BUT in the long term return on this short-term investment.
Improved on-stream factors and Product Quality
Better Product Availability for the marketplace
Benefits of Safety
Lower insurance costs
Higher Morale of personnel
More objective project evaluation
Improved public and personnel relations.
Reminder
Under no circumstances should the safety function of an organization report to production, marketing, or other line business functions that might have conflicting goals.
Reminder
Safety Personnel must communicate with the entire organization to promote safety awareness and knowledge.
Steps
Identify first the risk
Identify those alternative actions that can be used
Risk analysis and Management1. Starts with hazard identification
- check the material safety datasheets
Delphi Method
- ranks the hazards according to their probable occurrence and severity.
Risk analysis and Management2. All practical steps should be made to
reduce both the probability and severity of the risk
By integrating risk management in the process and plant design, risk can be managed in a practical and effective manner
Industrial process design and operation A desirable process and plant safety program
starts with a well conceived process and plant design
Material datasheets should be reviewed to identify hazards each chemical represents and the methods to control it
Data and Information for chemical hazard assessment
Name and chemical composition
Regulatory requirements
Physical and chemical property data
Fire and explosion data
Reactivity data
Health information
Spill, leak, and disposal procedures
Special protective equipment and precautions
Information Gathering
Process Chemistry conversion from raw materials to desirable
products can create or reduce hazards in the process and
plant design
Process chemistry in process and plant design
Chemical raw materials and catalysts
Chemical reactions and kinetic data
Process operating parameters and ranges
Preliminary process flow diagram
Material, product, and waste inventories
Technology information for process and plant designProcess, by-products and wastes produced
Process technology to be used
Plant capacity
Process flow diagrams
Process operating variables
Selection of the plant site
Hazard identification and safety control
Waste identification and safety control
Process control techniques
Equipment specifications
Government permit requirements
Piping and instrumentation diagrams
Operational information for process and plant design
Construction timetable
Inspection and testing of equipment and instrumentation
Personnel and training requirements
Startup and troubleshooting of potential problems
Debottlenecking opportunities
Operations, maintenance, and emergency procedures
Procedures for upset operating conditions
Procedures for safety and environmental audits
Information Gathering
Piping and instrumentation diagram (P&ID) A diagram which shows the interconnection of
process equipment and the instrumentation used to control the process.
Sample P&ID
Water Heater Facility
Plant Operation
Normal plant operation operating within desirable operating ranges
Significant deviation from the normal operation would result to an upset condition
Safety equipment and systems for process and plant design
Fire protection
Gas and vapor detection
Alarm and interlock
Pressure relief and vent
Isolation of equipment and plant
Emergency relief and vent
Emergency and backup services
Plant Operation
Critical: control deviations restore upset conditions to normal operation
* In start-up period major deviations from normal operations may be expected
Plant Operation
Successful start-up periods are enhanced by training of operators and process design that anticipated start-up problems before they occur.
During the shutdown phase, deviation outside normal operation can also be expected.
A smooth shutdown greatly assist a successful start-up.
Mechanical Integrity of Process Equipment Design, fabrication, installation, and
maintenance affect safety Specified construction materials should be
used in fabrication and maintenance All equipment used in the operating facility
should be fabricated in accordance with design specifications
Mechanical Integrity of Process Equipment When design specifications are
compromised, probability of accident is increased
Inspect, verify and test to confirm reliability Perform testing prior to start-up and
periodically thereafter Place procedures where hazardous materials
are involved
Mechanical Integrity of Process Equipment During maintenance operations, facility is
vulnerable to the creation of a hazardous conditions
Design considerations should be given for different kinds of work during operation
Safety relief devices
Process Hazard Analysis
Hazard analysis is a study to identify, analyze, and evaluate the risk of hazards associated with a process or operating facility
Used to identify limitations in siting, design, layout, and operation of facilities
Improve the safety and management of risk at operating facilities
Process Hazard Analysis
OSHA US Environmental Protection Agency US Department of Transportation Have promulgated regulations concerning
safety and health hazards These regulations addresses the probability,
severity, and consequences
Process Hazard Analysis
Severity – What can go wrong? How bad can it get?
Probability – How likely is it to occur? Consequences – What are the impact?
Consequences of Hazard IdentificationMaterial Safety Data Sheets Laboratory experiments Research and Development
HAZARD ANALYSIS TECHNIQUES
Hazard analysis are used to determine the potential for deviations from or weaknesses in the system design that could pose a hazard to personnel and/or equipment.
Hazard Analysis
Hazard Analysis should identify risks, methods to reduce risk, and any actions needed to ensure that the equipment can be operated and maintained safely.
Hazard Analysis Techniques
What-if Check list What-if/Check list Hazard and operability study (HAZOP) Failure mode and effects analysis (FMEA) Fault tree analysis Appropriate equivalent methodology
What-if
brainstorming techniques, in the form of ‘What If’ questions are used to identify possible deviations and weaknesses in design.
‘What If’ hazard analyses can be used to determine system compliance with SEMI S2 requirements to verify that “no single point of failure or operational error should allow immediate exposure of personnel, facilities or community to hazards or directly result in injury, death or equipment loss.”
What is SEMI S2 Requirements?
Safety Guidelines for Semiconductor Manufacturing Equipment
defines minimum performance-based safety requirements that address a number of hazards, including chemical, electrical, fire safety, sound, radiation, mechanical, and seismic.
What-if
Caution: ‘What If’ hazard analyses are based on brainstorming. Their thoroughness and accuracy are dependent upon the composition and expertise of the team performing the analysis. In addition, the ‘What If’ hazard analyses stops at a single point of failure and does not investigate the system further. (i.e., This method would not evaluate a series of failures and the potential consequence of this series.)
What if (example)
What if Consequence Comments
Material A does not flow to reactor?
Unreacted B will contaminate Product C
Alarm and shot off valve B
What if equipment temperature exceeds its limit?
Equipment failure.
Meltdown of components.
Off the equipment and increase the cooling system.
Checklist Analysis
It is used for step of the process. Time consuming in development Can be apply also to complex processes with
similar hazards. Also like what-if in development
Example of checklist
Checklist Answer Comments
Is each delivery of material B checked for contamination?
Yes Supplier of material B has been reliable.
Is the particle count in the room exceeds 3ppm^3
No The room can be use on process.
Combined what-if and checklist More broad-based hazard assessment
technique. Involve brainstorming also
Hazard and Operability analysis (HAZOP) Systematic study of each process element
and requires thorough examination of process-flow diagrams.
Pant operation => improved plant efficiency Uses guide words
Failure Mode and Effect Analysis (FMEA) Begins of all listing the Equipments and
process components of the system under study
More applicable to projects that are well into design phase.
Contains failure mode, consequences, safeguards, recommended action
Fault Tree Analysis
Begins with graphical diagrams of all sequence of events that could result on incidents, accidents, or exposure.
Uses logic symbols and event symbols
Fault tree analysis symbols
TOP EVENT
OR GATE AND GATETransfer IN-OUT
BASIC EVENT
UNDEVELOPED EVENT
Fault Tree Analysis Example
SYSTEM FAILS
C D
A B
Personnel Motivation and Training Operations and Maintenance Personnel
needs training Highly trained and skilled personnel are
excellent resource for improving safety and productivity.
Outside contractors are also to be considered
Well-conceived process control system should reflect a balance between:
Human Control Reflects human capability at a particular time when the
response is required
Hardware Control Reflects upon the hardware design and mechanical
integrity at a particular point of demand
Human Errors
Errors of Omission Employee forgot to execute a required task
Errors of Commission Employee Performed the task but did it incorrectly
Errors of Sequence Employee did the task out of order with the required
sequence Errors of Timing
Employee did the task either too fast or slow
Operator-Induced Error Employee has the knowledge to make the correct
decision but acts incorrectly System-Induced Error
Created by integration of incompatible components into a total system
Design-Induced Error Results from faulty equipment design, fabrication
or installation
Input Errors Caused by typographical errors associated with
data or information Low Stress Errors
Cause by a lapse of memory during a normal environmental condition
High Stress Errors When employees make wrong decisions in
life-threatening situations
Process and Plant Modification Change It should not result in errors that could lead to
accidents
Safety program at the operating facility should have procedures to manage modifications
Hazard Analysis should be performed
Incident Investigation and Safety Audits Near-miss Incidents should be studied
Safety Audits are used to verify compliance with regulatory standards
Used to protect the safety and health of the employees, surrounding communities and environment
Safety Audits
Review of Relevant Documentation Review of Process Safety Information Inspection of Operating Facilities Interviews with selected plant personnel