Office Ergonomics 2005

8/8/2019 Office Ergonomics 2005

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Office Ergonomics


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Office Work &

Human/Computer Interactions

Work station design

Posture

Keyboards Software/human interactions

Human Behavior


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Office Work &


Early studies 1980s

Eye problems

Shoulder problems Lower back problems

Neck strain

Hand & wrist problems


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Office Work &


1991 study of 420 medicalsecretaries

63 % reported neck/shoulder pain

51% low back pain

30 % hand/wrist pain

15 % elbow pain


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Whos At Risk?

Nearly everyone, but women report moreincidents of discomfort

Low motivation

Poor workstation design

Many short term studies, few long term orindependent studies.


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Are some people at greater risk

than others?

Some researchers think so.

Studies quoted on Cornells ergo web site

link repetitive motion injuries to

Working with the wrists in deviated postures for any

reason: causes compression of the median nerve

Static postures, especially using a pinch grip to holdsomething in place


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Some studies have shown greater risks for people

who are Pregnant

Obese

Lack general physical capabilities, such asstrength

People who feel as if they lack control over workpace, environment, and communication


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Prevention is crucial to Cost

Containment

Evaluate all contributing factors

=Hazard Identification

EnvironmentEnvironment

WorkersWorkers Equipment/MaterialsEquipment/Materials

Task/ProcessesTask/Processes


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Hazard Prevention

Neutral positioning

Workstation design

Work/rest periods

Task rotation

Exercise


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What is neutral positioning?

Non-stressed postures

Relaxed, right angles at

Knees, hips and elbows Wrists straight rather than flexed (down) or

extended (up)

Lower and upper back supported


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Computer Workstations

Key ElementsKey Elements

Good Working PositionsGood Working Positions

Work ProcessWork ProcessWorkstation EnvironmentWorkstation Environment

Workstation ComponentsWorkstation Components


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Good Working Postures

Hands, wrists, and forearms are straight, in-line and

roughly parallel to the floor.

Head is level, or bent slightly forward, forward facing, and

balanced. Generally it is in-line with the torso.

Shoulders are relaxed and upper arms hang normally atthe side of the body.

Elbows stay in close to the body and are bent between 90

and 120 degrees.

Feet are fully supported by floor or footrest.

Backis fully supported with appropriate lumbar support

when sitting vertical or leaning back slightly.

Thighs and hips are supported by a well-padded seat and

generally parallel to the floor.

Knees are about the same height as the hips with the feetslightly forward.


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WorkProcess

Task Organization

Impacts repetition

Prolonged periods of activity

Medical awareness & training


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Work Environment

Lighting

Glare

Ventilation Noise


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Workstation Design

Chairs

Monitors

Keyboards

Pointer/Mouse Wrist/Palm Support

Document Holders

Desks

Telephones Footrests


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Elements of good work

station design

Adjustable chairs

Keyboard height and angle

Avoid sharp edges

Monitor height and angle Glare, poor contrast, etc. are risk factors


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Chairs

Ideas about correct posture go back to 1884

Upright vs. backward leaning, pressure ondisks, lower back

Chair provides support for upper and lowerback


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Need to be adjustable in many differentdirections

Height

Tilt of seat pan Angle of back

Provide lumbar support

Adjustable arms

Capacity, seat width

Chairs


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Ergonomic Chairs

Chair Specifications

Seat Height

Backrest

Seat Size

10 Standard Adjustments

Pneumatic Seat Height

Seat Angle or Tilt

Seat Angle Tension Control

Backrest AngleBackrest Height

Backrest Depth

Inflatable Lumbar

Armrest Height

Armrest Rotation/Swivel

Armrest Width

Small Seat

Minimal Contour

Seat Height: 16.5" - 21.5"

Backrest: 19.5"W x 22.5"HSeat Size: 19"W x 17"D


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Ergonomic Chairs


Seat

Height

Backrest

Seat Size

18" - 23"

24"W x

26"H

26"W x

21"D


Seat

Height

Backrest

Seat Size

16.5" - 21.5"

19.5"W x

22.5"H

22.5"W x 17"D

Deep Contoured Seat, KneeTilt Available Big & Tall


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Monitors

Viewing Distance: 20-40

Viewing Angle: 15-20 degrees

below horizontal

Viewing Time

Viewing Clarity


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Keyboards

The objective is to keep the hands and wrists in as

neutral a position as possible

Adjustments, may include tilting or not tilting the

keyboard, wrist rests in front of the keyboard, andrepositioning the entire body

Alternative shapes of keyboards may help: Split

Tented/Angled

Negative Slope

Supportive

Scooped Keep in mind

Keyboard Placement Height & Distance

Design & Use


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Pointer/Mouse Interactions

For CAD operators

Thumb and forefinger problems

Change kind of mouse Thumb joint pain, switch to Uniballor

three-finger mouse

Keep in mind

Pointer Placement

Pointer Size, Shape, & Settings


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Wrist/Palm Supports

In general, research supports the idea of resting thehands on some kind of a surface during keying pauses.

The use of wrist rests has been associated with reduced

muscle activity in the arms and shoulders, straighterwrist postures, comfort, and preference.


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Wrist/Palm Supports

Some research suggests that wrist rest users sit in a somewhatmore reclined posture than people without wrist rests, which isknown to be comfortable and healthy for the back

However, wrist rests are not without potential problems

Caution


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Wrist/Palm Supports

Not all studies of wrist rests show positiveeffects

Use of wrist rest causes the fluid pressure in the carpaltunnel to rise, sometimes significantly

Use of convex wrist rests, which concentrate pressurein a small area, are less desirable than broad, flat ones

Benign cysts apparently have been caused by constantpressure on the wrist

Typists should use them during keying pauses,not during keying, in order to have free handand arm movement and to reduce the amountof time the wrist is compressed


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Document Holder

Are designed to minimize eye and neckmovement by keeping your documents at theproper viewing level


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Desks

Work Surface Depth

Location of Frequently Used Devices Should beLocated in Repetitive Access Zone

Recommended Zones for Workplace Components


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Telephones

Head sets can help avoid neck andshoulder strain for telephone use.


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Footrests

Reduces leg strain and promotescirculation

Reduces strain on lower back

Should position your knees to roughly a90 degree angle


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Other ConsiderationsOther Considerations


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Work/rest periods

An element of a goodAn element of a goodprevention strategyprevention strategy

Provide regular breaks by inserting a different kindof task into the routine

Some studies recommend 5 minutes of rest per hourof typing

Other studies recommend 15 minutes of rest perfour hours of work.


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Task Rotation

Alternate other kinds of office tasks,such as filing, copying

Caution: May be just as repetitive as typingand use the same motions and muscles

However, more productive and feel less like

an interruption than just a break


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Task Rotation & Breaks

Some companies have actually installedsoftware that shuts down the system forregular breaks

Other companies have organized or signaledbreaks

These can be aggravating, as they interrupt atask in progress


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Eye Strain

Eyestrain is the most common complaintfrom computer users

Intensive use Software Interactions

Inadequate or detrimental lighting andmonitor conditions Distance to monitor

Ambient lighting

Glare

Pre-existing eye conditions, including thoseyou may not be aware of

Stress


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A study conducted by Cornell UniversityA study conducted by Cornell University

Showed that there was an increase in the numberof cases of repetitive stress injuries after new and

hard to use software was introduced

Especially if there were multiple screens or fieldson the monitor simultaneously

Eye Strain


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Prevention

Task rotation

Get a professional eye examination

Control the lights & the monitor

Enough light on documents

Eliminate glare

Rearrange the workstation

Anti-glare screen

Eye Strain

S l i Offi E i


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Solving Office Ergonomic

Problems

Evaluate non-work stressors

Evaluate work stressors Use checklists

Use workers compensation claim data

Use personal interviews/discomfort surveys Conduct job safety analysis

Observation

Measurements

Implement solutions

ProvideEmployee Training


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Analyze a problem job

Think about the role behavior plays in ensuringproper use and comfort.

A claim of ergonomic designwill not ensure

improved use or comfort, (or reduced risk factors) ifbehaviors have been ignored

For instance, if workers will not use the new tool, it

cannot reduce the risk


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Questions?Questions?

Documents

Office Ergonomics 2005