2Office Work & Human/Computer Interactions Work station designPostureKeyboardsSoftware/human interactionsHuman Behavior
3Office Work & Human/Computer Interactions Early studies 1980’sEye problemsShoulder problemsLower back problemsNeck strainHand & wrist problems
4Office Work & Human/Computer Interactions 1991 study of 420 medical secretaries63 % reported neck/shoulder pain51% low back pain30 % hand/wrist pain15 % elbow pain
5Who’s At Risk?Nearly everyone, but women report more incidents of discomfortLow motivationPoor workstation designMany short term studies, few long term or independent studies.
6Are some people at greater risk than others? Some researchers think so….Studies quoted on Cornell’s ergo web site link repetitive motion injuries to…Working with the wrists in deviated postures for any reason: causes compression of the median nerveStatic postures, especially using a pinch grip to hold something in place
7Some studies have shown greater risks for people who are… PregnantObeseLack general physical capabilities, such as strengthPeople who feel as if they lack control over work pace, environment, and communication
8Prevention is crucial to Cost Containment Evaluate all contributing factors=Hazard IdentificationTask/ProcessesEnvironmentWorkersEquipment/Materials
14Computer Workstations Key ElementsGood Working PositionsWork ProcessWorkstation EnvironmentWorkstation Components
15Good Working PosturesHands, 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 at the 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.Back is 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 feet slightly forward.
16Work Process Task Organization Impacts repetition Prolonged periods of activityMedical awareness & training
19Elements of good work station design Adjustable chairsKeyboard height and angleAvoid sharp edgesMonitor height and angleGlare, poor contrast, etc. are risk factors
20Chairs Ideas about correct posture go back to 1884 Upright vs. backward leaning, pressure on disks, lower backChair provides support for upper and lower back
21Need to be adjustable in many different directions ChairsNeed to be adjustable in many different directionsHeightTilt of seat panAngle of backProvide lumbar supportAdjustable armsCapacity, seat width
22Ergonomic ChairsChair SpecificationsSeat Height Backrest Seat Size10 Standard AdjustmentsPneumatic Seat HeightSeat Angle or TiltSeat Angle Tension ControlBackrest AngleBackrest HeightBackrest DepthInflatable LumbarArmrest HeightArmrest Rotation/SwivelArmrest WidthSmall SeatMinimal ContourSeat Height: 16.5" " Backrest: 19.5"W x 22.5"H Seat Size: 19"W x 17"D
23Ergonomic Chairs Deep Contoured Seat, Knee Tilt Available Big & Tall Chair SpecificationsSeat Height Backrest Seat Size16.5" " 19.5"W x 22.5"H 22.5"W x 17"DChair SpecificationsSeat Height Backrest Seat Size18" - 23" 24"W x 26"H 26"W x 21"DDeep Contoured Seat, Knee Tilt AvailableBig & Tall
28Keyboard Placement – Height & Distance KeyboardsThe objective is to keep the hands and wrists in as “neutral” a position as possibleAdjustments, may include tilting or not tilting the keyboard, wrist rests in front of the keyboard, and repositioning the entire bodyAlternative shapes of keyboards may help:SplitTented/AngledNegative SlopeSupportiveScoopedKeep in mindKeyboard Placement – Height & DistanceDesign & Use
33Pointer/Mouse Interactions For CAD operatorsThumb and forefinger problemsChange kind of mouseThumb joint pain, switch to “Uniball” or three-finger mouseKeep in mindPointer PlacementPointer Size, Shape, & Settings
34Wrist/Palm SupportsIn general, research supports the idea of resting the hands 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, straighter wrist postures, comfort, and preference.
35Wrist/Palm Supports Caution Some research suggests that wrist rest users sit in a somewhat more reclined posture than people without wrist rests, which is known to be comfortable and healthy for the backHowever, wrist rests are not without potential problemsCaution
36Wrist/Palm SupportsNot all studies of wrist rests show positive effectsUse of wrist rest causes the fluid pressure in the carpal tunnel to rise, sometimes significantlyUse of convex wrist rests, which concentrate pressure in a small area, are less desirable than broad, flat onesBenign cysts apparently have been caused by constant pressure on the wristTypists should use them during keying pauses, not during keying, in order to have free hand and arm movement and to reduce the amount of time the wrist is compressed
37Document HolderAre designed to minimize eye and neck movement by keeping your documents at the proper viewing level
38Desks Work Surface Depth Location of Frequently Used Devices Should be Located in Repetitive Access ZoneRecommended Zones for Workplace Components
43An element of a good prevention strategy Work/rest periodsAn element of a good prevention strategyProvide regular breaks by inserting a different kind of task into the routineSome studies recommend 5 minutes of rest per hour of typingOther studies recommend 15 minutes of rest per four hours of work.
44Alternate other kinds of office tasks, such as filing, copying Task RotationAlternate other kinds of office tasks, such as filing, copyingCaution: May be just as repetitive as typing and use the same motions and musclesHowever, more productive and feel less like an interruption than “just a break
45Task Rotation & BreaksSome companies have actually installed software that “shuts down” the system for regular breaksOther companies have organized or signaled breaksThese can be aggravating, as they interrupt a task in progress
46Eyestrain is the most common complaint from computer users Intensive useSoftware InteractionsInadequate or detrimental lighting and monitor conditionsDistance to monitorAmbient lightingGlarePre-existing eye conditions, including those you may not be aware ofStress
48A study conducted by Cornell University Eye StrainA study conducted by Cornell UniversityShowed that there was an increase in the number of cases of repetitive stress injuries after new and hard to use software was introducedEspecially if there were multiple screens or fields on the monitor simultaneously
49Eye Strain Prevention Task rotation Get a professional eye examination Control the lights & the monitorEnough light on documentsEliminate glareRearrange the workstationAnti-glare screen
50Solving Office Ergonomic Problems Evaluate non-work stressorsEvaluate work stressorsUse checklistsUse workers’ compensation claim dataUse personal interviews/discomfort surveysConduct job safety analysisObservationMeasurementsImplement solutionsProvide Employee Training
51Analyze a problem jobThink about the role behavior plays in ensuring proper use and comfort.A claim of “ergonomic design” will not ensure improved use or comfort, (or reduced risk factors) if behaviors have been ignoredFor instance, if workers will not use the new tool, it cannot reduce the risk