ergonomics and osha 24-apr-2006

7/30/2019 Ergonomics and OSHA 24-Apr-2006

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Office Ergonomics and OSHA

Cecilia R. AragonIEOR 170

UC Berkeley

Spring 2006


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Spring 2006 IEOR 170 2

Acknowledgments

Jeffrey Chung, Lawrence Berkeley National

Laboratory ergonomics program manager

Cathy Rothwell, US Navy ergonomics program

manager


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OSHA - Occupational Safety and

Health Administration

Occupational Safety and Health Act of 1970

Purpose:

setting standards conducting workplace inspections to ensure

that employers are complying with the

standards and providing a safe and healthful

workplace


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Who is Covered by OSHA?

In general (with some exceptions), all employers

and their employees in the 50 states, the District

of Columbia, and Puerto Rico.


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Who is Covered by OSHA?

All employers and employees except: Self-employed persons

Farms at which only immediate members of the

farmer's family are employed

Working conditions regulated by other federal

agencies under other federal statutes. This category

includes most employment in mining, nuclear energy

and nuclear weapons manufacture, and many

segments of the transportation industries.

Employees of state and local governments(unlesscovered by an OSHA-approved state program)


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OSHA Standards

Employers must protect workers on the job.

Employers have the responsibility to know relevant

standards and comply.

Compliance may include providing personal protectiveequipment for employees.

Employees must also comply with OSHA rules and

regulations.


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Federal OSHA Requirements

Access to Medical and Exposure Records Employers must grant employees access to medical records and

records on employees exposure to toxic substances.

Personal Protective Equipment

Employers must provide employees at no cost personal protective

equipment (e.g. protective helmets to prevent head injuries in

construction and cargo handling work, eye protection, hearing

protection, hard-toed shoes, special goggles, etc.)

Hazard Communication

Employers must conduct hazard evaluation of the products theymanufacture or import. If hazardous, containers of the material must be

labeled and accompanied by a material safety data sheet(MSDS).

Employers must train their employees to recognize and avoid material

hazards.


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State Programs

States with OSHA-approved job safety and

health programs must set standards that are at

least as effective as the equivalent federal

standard. Most of the state-plan states adopt standards

identical to the federal ones.


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Cal/OSHA Responsibilities

Enforce California laws and regulationspertaining to workplace safety and health

The Cal/OSHA Enforcement Unit conducts inspections of

California workplaces based on worker complaints,

accident reports and high hazard industries.

Provide assistance to employers and workers

about workplace safety and health issues

The Cal/OSHA Consultation Service provides assistance

to employers and workers about workplace safety and

health issues, and develops educational materials on

workplace safety and health topics.


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For More Information

OSHA

http://www.osha.gov

http://www.ehso.com/oshaoverview.php

Cal/OSHA

http://www.dir.ca.gov/dosh/dosh1.html

http://www.dir.ca.gov/occupational_safety.html


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Ergonomics


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What is Ergonomics? ergonomics \, rg-go-'nm-iks

Ergonomics is derived from two Greek words

Ergon meaning work

and

Nomos meaningprinciples or laws

Ergonomics = The Science of Work

Ergonomics is not a new science, although the term has

become more common lately. The phrase was first coined

in 1857.

[Rothwell]


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Common Definitions

Ergonomics is essentially fitting the workplace to the

worker. The better the fit the higher the level of safety

and worker efficiency. Fitting the Task to the Human ~Grandjean 1990

Ergonomics removes barriers to quality, productivity and

human performance by fitting products, tasks, andenvironments to people. ErgoWeb.com

What is Ergonomics? ergonomics \, rg-go-'nm-iks

[Rothwell]


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What are the consequences

of poor ergonomics?

Why are we hearing about ergonomics now? Arethere new hazards at work? No!

Consequences of poor workplace design were first documented

in the 17th century.

Have you ever heard of these?

Historic Occupational Disorders - house-maids knee, washerwomans thumb, writers cramp, data-processing disease,clergymans knee, nuns bursitis, weavers bottom, dustmansshoulder, tailors ankle

[Rothwell]


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Do these historic occupational

disorders still exist? Yes!

They are part of a broad category of injuries and disorders

called Musculoskeletal Disorders (MSDs). MSDs are not usuallycaused by acute trauma, but occur slowly over time due to repetitive

injuries to the soft tissues (muscles, tendons, ligaments, joints, cartilage)

and nervous system.

MSDs can happen to anyone from office workers and

industrial employees to athletes and hobbyists.

Before Improved


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Do these historic occupational

disorders still exist? Yes!

Work-Related Musculoskeletal Disorders

(WMSDs) are MSDs that are caused or made worse bywork methods and environment. They occur when the

physical capabilities of the worker do not match thephysical requirements of the job.

Common MSDs:

Tendonitis, Epicondylitis(Tennis or Golfers Elbow), Bursitis,Trigger Finger, Carpal Tunnel Syndrome, Back Strain

Before Improved[Rothwell]


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What are aliases for WMSDs?

Work-related MSDs go by many other names:

Repetitive Strain or Stress Injury (RSI)

Repetitive Motion Injury (RMI) Cumulative Trauma Disorder (CTD)

Overuse Syndrome

Activity-related Pain Syndrome

Ergonomics can help prevent MSDs that are caused or aggravated byworking conditions

[Rothwell]


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MSDs

Carpal Tunnel Syndrome

Cubital Tunnel Syndrome

Tendonitis and Tenosynovitis

Trigger Finger

Epicondylitis

De Quervains Tenosynovitis

Wrist Ganglion Cyst

[Chung]


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Tendonitis

Normal tendon glides smoothly in a tendon sheath

When under pressure, the capillary flow to the sheath

is temporarily interrupted.

When blood supply returns, swelling occurs.

[Chung]


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Double Crush Syndromes

Multiple points of pressure will have cumulative effects

on axonal flow.

[Chung]


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Carpal Tunnel, Inside of Wrist

Inside view of right wrist Yellow nerve crosses

under flexor retinaculum

Nerve has to share the

space with nine tendonsand tendon sheaths.

[Chung]


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Median Nerve (Carpal Tunnel)

[Chung]


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Should Employers Care About

Ergonomics?

Average 2003 cost for LBNL computer-related workerscompensation claims: $23,745.

[Chung]


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Office Ergonomics The science of "designing the job to fit the

worker, not forcing the worker to fit thejob."

Ergonomics covers all aspects of jobs:

physical stresses placed on joints,

muscles, nerves, tendons, bones, etc.

environmental factors affecting hearing,

vision, and general comfort and health.

WORK CULTURE

ENVIRONMENT

EQUIPMENT

TASKS

USER

Enhance comfort

Increased productivity

Improve job satisfaction and morale

Reduced musculoskeletal discomfort,workinjuries/illnesses

[Chung]


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Designing for the Worker

Anthropometrics

branch of ergonomics that deals with the

measurement of body dimensions

anthropometric data is used in the design ofequipment and products to make them fit the height

and reach of most of the potential population

Gaussian distribution, design to 5%

Consider range of size, age, and physical abilitywhen designing

Americans with Disabilities Act (ADA)


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Ergonomic Risk Factors Awkward

positions Static postures

Repetitivemotion

Forcefulexertion

Contactpressure


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At Risk Thresholds

Per OSHA, certain situations create MSD risks: Performing same motion pattern every few secondsfor > 2 hours continuously or 4 hours daily.

Maintaining non-neutral (unsupported, static/fixed or

awkward posture > one (1) hour continuously or four(4) hours daily.

Forceful hand exertions > two (2) hours daily.

Unassisted frequent or heavy lifting

Boredom and monotony

[Chung]

Do you have these risks?


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Warning Signs

Watch for: Tingling or numbness in hands

Pain: sharp, dull or burning

sensation

Stiffness, reduced range of

motion in arms, wrists

Clumsiness, loss of grip strength

or coordination

Visual fatigue, watery eyes,dryness.

[Chung]


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Three Stages of CTDs

Stage One aches and tiredness during working hours

symptoms settle overnight or days off work

no reduction in work performance

condition may persist for weeks or months and is reversible

[Chung]

Stage Two

symptoms start early in work shift and dont settle overnight

sleep may be disturbed

capacity to perform repetitive work is reduced

condition usually persists for months


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Three Stages of CTDs

Stage Three symptoms persist even at rest

pain occurs with non-repetitive movements of

affected area sleep is disturbed

person unable to perform even light duties and has

difficulties with other manual tasks

[Chung]


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Workstation Setup: Neutral Posture1.Use a good chair and sit back

2. Top of monitor 2-3" (5-8 cm)

above eyes

3. No glare on screen

4. Sit at arms length

5. Feet on floor or footrest

6. Use a document holder7. Wrists flat and straight

8. Arms and elbows close to

body

9. Center monitor and keyboard

in front of you10. Use a negative tilt keyboard

tray

11. Use a stable work surface

12. Take frequent micro-breaks


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Workstation Setup: Neutral Posture

Work within your normalrange of motion

Other Office Items

Telephones

Staplers

Staple removers

Letter openers

Hole punches

Pens for writing

tasks

[Chung]


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Sitting Risk Factors

Neutral

Posture

Slumped

Posture[Chung]


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Posture and Spinal Stresslbs

660

550

440

330

220

110

Load on 3rd Lumbar Disc in 155-pound male

[Chung]


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Reaching/Range of Motion Factors

Elbow Arm/Wrist

Shoulder

Back

Elbows in

Face the

object you are

reaching for.

[Chung]


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Watch the Hand Movements

DON'T restyour wrists

on the

desktop

DO let your

wrists float

[Chung]


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Watch the Hand Movements

SAFER

[Chung]


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Contact Pressure

Soft tissue compression

(muscles, nerves & blood vessels)

[Chung]


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Ergo Accessories - Chair

Features:

Height

Seat pan

Backrest height Backrest tilt

Armrest height

- Armrest width(chairs may have none, some, or all

of these).

[Chung]


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Ergo Chairs & AccessoriesFeatures/Adjustments:

Height Seat pan (width/depth)

Backrest height

Backrest tilt

Backrest tension

Armrests

Casters

[Chung]


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Monitor Accessories

Screen height at eye

level (exception:

bifocals and trifocal

lens wearers). Screen distance

about arms length

away.

Room lighting -avoid

backlight, shadows or

reflective glare.[Chung]

K b d d A i


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Keyboards and Accessories

Voice-activated

[Chung]
http://www.ergo-2000.com/ergo2000/showdetl.cfm?&DID=6&User_ID=442232&st=8298&st2=-35670889&st3=59199202&Product_ID=707&CATID=36


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Input Devices - Pointing Devices

[Chung]


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Telephone Use

Phone evaluation: reach,

placement, call frequency vs.duration, multi-tasking, etc.

Cradle with neck/shoulder

Cordless unit / motorized unit

[Chung]
http://www.amazon.com/exec/obidos/tg/stores/detail/-/electronics/B00004WFYM/103-0919291-5287040


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Document Holders

Place hardcopy beside or in front of monitor to

reduce neck twisting.

[Chung]


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Notebooks, Laptops, Etc. Laptops can cause:

Awkward arm position Neck flexion to view the screen

Neck pain from carrying/transporting laptops

Fixes:

Use docking station and external input devices. Acquire portable devices and accessories.

[Chung]

P t ti l At Ri k C diti ( )?


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Potential At-Risk Condition(s)?Guidelines: Shoulders relaxed/arms close to body side; safe

reaching distance for mouse; neutral sitting Right hand on mouse even

when not actively mousing

(median nerve).

Left lean supporting body

weight with arm; spine out

of natural alignment

Ulnar nerve compression

(non-mousing elbow)

Static muscle loading: right

shoulder abduction, wrist

extension, flexed left arm

[Chung]

P t ti l At Ri k C diti ( )?


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Potential At-Risk Condition(s)?

[Chung]

Potential At Risk Condition(s)?


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Potential At-Risk Condition(s)?

[Chung]

E i H d B f


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Ergonomic Hazards - Before

[Chung]

E i C t l Aft


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Ergonomic Controls - After

[Chung]

E i H d B f


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Ergonomic Hazards - Before

[Chung]


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Ergonomic Controls - After

[Chung]

C t W k t ti C id ti


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Computer Workstation Considerations

DiscomfortTelephone Use

Input Devices(keyboard and pointing)

Task BreaksMonitor and Vision

Work StyleWork Surface

LaptopChair

WritingLightingDocument UseLayout

[Chung]

Individual Issues


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Computer Workstation

Order of adjustments is important

Adjust chair first

Then adjust keyboard

Finally, adjust monitor No single right way to sit

ergonomics and osha 24-apr-2006

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