Introduction to Office Ergonomics

1. Introduction to Office Ergonomics In addition to this online slideshow, the OH&S Unit can run face-to-face training sessions that includes practical instruction in how to set up a workstation. Call x35666. 1 Occupational Health & Safety Unit

2. What is Ergonomics Ergonomics refers to the interaction between the individual, their work and work environment so that human capabilities are reinforced without exceeding human limitations. 2 Occupational Health & Safety Unit

3. Ergonomics is involved in the interaction of the three components of all work tasks: • The Work • The Worker • The Workspace 3 Occupational Health & Safety Unit

4. An example of poorly set up workstations. 4

5. Another example. 5

6. What Does Ergonomics Aim To Do? The aim of Ergonomics is to minimise the mismatch that occurs between the person and the job or match the capabilities of humans and the requirements of the job they are expected to perform. Where possible, all attempts should be made to fit the job to the person. 6 Occupational Health & Safety Unit

7. Workplace Injuries • Back pain • Shoulder and arm pain • Headaches Providing a telephone headset can reduce the incidence of headaches caused by cradling the phone in the neck while taking a message. 7 Occupational Health & Safety Unit

8. Lighting • Workers should be able to see clearly. • Safely perform their work. • Measurement of light levels is in lux. • Examples of levels for reference material: • good, simple detail - 240 Lux • average detail - 320 Lux • poor, fine detail - 600 Lux More information on lighting issues later on in the slideshow. 8 Occupational Health & Safety Unit

9. Work Rest • The length of the pause and how often they are taken depends on the work, the person and other factors • Frequent short pauses are preferable to infrequent longer pauses. Staff should be encouraged to take regular rest breaks from a given task, even if this means changing the task. 9 Occupational Health & Safety Unit

10. Body Mechanics • Tendons and ligaments cross over joints to form levers. • The best, strongest and safest work position is when the joints are at mid range. 10 Occupational Health & Safety Unit

11. Muscle Activity • Dynamic muscle activity – when joints are at mid-range. • Static muscle activity – when joints are at their extreme range. 11 Occupational Health & Safety Unit

12. Above, all joints at mid-range causing dynamic muscle loading. This is a ‘comfortable’ posture. 12

13. Occupational Overuse Syndrome A collective term for a range of conditions characterised by discomfort or persistent pain in muscles, tendons and other soft tissues with or without visible symptoms. 13 Occupational Health & Safety Unit

14. Contributing Factors • Repetitive movement • Sustained or constrained postures • Forceful movements • Incentive schemes that influence work rate • Tight deadlines • Dependent on the duration and frequency of the tasks being performed. 14 Occupational Health & Safety Unit

15. How Injuries Occur Static Muscle Contraction  Muscles Tense  Blood Flow is reduced  Muscle Nutrition is reduced  Waste products (lactic acid) build up  Muscle pain and fatigue  Injury/Disability 15 Occupational Health & Safety Unit

16. Efficient Posture • Places minimal or balanced stress on different body parts. • Requires minimal muscular effort to sustain. • Is perceived as comfortable by the individual. See example on Slide 12. 16 Occupational Health & Safety Unit

17. Efficient Posture It is important to reinforce that all persons should vary posture regularly and usually between sitting and standing/walking. For example, rather than place a printer on a desk, locate it where the staff member has to get up and walk to retrieve printed documents 17 Occupational Health & Safety Unit

18. Setting Up The Workstation • Work reach • Most frequently used items should be within approximately 350-450mm. • Less used items can be at a further distance. This is a fundamental of ergonomics and eliminates unnecessary work. 18 Occupational Health & Safety Unit

19. Work surface height - standing • Type of work performed. • Items being handled. • Tools and controls used • Height of the workers When setting up an area such as a bench or counter for work to be performed while standing the above factors should be taken into consideration. 19 Occupational Health & Safety Unit

20. Work surface height - standing • Benches for collating/stapling - below elbow height. • Benches for writing - above elbow height. • Recommended height for reception counters - 900-1100mm. • However, depends on worker’s height. Recommended dimensions for seated workstations can be obtained from the ‘toolbox’ on the OH&S web page. 20 Occupational Health & Safety Unit

21. Work surface height - sitting • Most workers can manage with a ‘fixed height’ work area if chair is adjustable. • Clerical Work - adjust chair height so top surface of desk is just above elbow level. • Keyboard work - home row of keyboard should be at approximately elbow height. • Allow adequate clearance for thighs. Instruction on how to adjust a chair can be found in the ‘toolbox’ on the OH&S web page. 21 Occupational Health & Safety Unit

22. 22 Seat Design Main principles are: • Spine should be supported using the backrest. • Static loading needs to be minimised. Occupational Health & Safety Unit

23. Seat Design • Features should include: • A backrest that is adjustable in angle and height and depth (not always available). • Cloth covered back and seat. • Curved front edge. 23 Occupational Health & Safety Unit

24. Seat Design • A good chair should have: • Gas strut for height adjustability • Five star base for stability. Kneeling chairs or exercise balls only to be used with written medical recommendation. 24 Occupational Health & Safety Unit

25. Seat Design “Executive” chairs have limited adjustability. 25 Occupational Health & Safety Unit

26. Seat Design • Arm rests are usually unnecessary. • Higher (drafting) chairs are usually harder to get up onto, the ring may cause tripping. • Castors are suitable for carpeted floors. • Glides to be used on hard floor surfaces. 26 Occupational Health & Safety Unit

27. Keyboards • Should be placed in front of the screen and directly in front of the user so that there is no need to twist or rotate to use it. • Should be placed near the front edge of the desk to reduce the reach distance. 27 Occupational Health & Safety Unit

28. Keyboards • ‘Feet’ at rear of keyboard should bekept in a lowered position to minimise the height and angle of the keyboard. • Where possible the keyboard should be moved away to allow the work surface to be used for other tasks such as writing. 28 Occupational Health & Safety Unit

29. Keyboards Split keyboards enable the joints to adopt a neutral posture while keying. 29 Occupational Health & Safety Unit

30. Keyboards 30 Another split keyboard. Occupational Health & Safety Unit

31. Wrist Rests • The use of wrist rests should be viewed with some caution. • The whole hand should move and not be kept in one position with the fingers reaching sideways. 31 Occupational Health & Safety Unit

32. Wrist supports (keyboard) 32 Occupational Health & Safety Unit

33. Wrist Supports (mouse) Mouse mats with, a pad for supporting the wrist, come in various shapes and styles. 33 Occupational Health & Safety Unit

34. Computer Screens • Top of the screen should be at horizontal eye level or lower, to minimise neck flexion. • Where large screens are used, may need some of screen above horizontal eye level. • Screen should be 350-750 mm from eyes. • Distance can vary with individual preferences. 34 Occupational Health & Safety Unit

35. Computer Screens • Workers wearing bifocals may tilt head back which may result in neck discomfort. • Multifocal lenses not suitable for VDU’s. • Workers may purchase glasses prescribed for computer, or position computer screen as low as possible and with an increase tilt backwards, if they have no other glasses. 35 Occupational Health & Safety Unit

36. Document Holders • Adjustable document holder may reduce forward neck inclination which may cause neck strain. • Documents should be placed level to screen or between keyboard and the screen. • Reading documents resting on the desk for prolonged periods may cause neck and shoulder strain. 36 Occupational Health & Safety Unit

37. Footrests • Footrests are required by people who are unable to place their feet flat on the floor when sitting in a correctly adjusted chair. • A correctly adjusted foot stool should allow the person’s legs to be at right angles with no pressure on the underside of the thighs. 37 Occupational Health & Safety Unit

38. Mouse and Trackball • The mouse should not place undue pressure on the wrist and forearm muscles: • Avoid stretching the arm in extension. • Place the mouse beside the keyboard. • Ensure mouse operates smoothly with the minimum of force. 38 Occupational Health & Safety Unit

39. Mouse and Trackball • Keep the arm by the side of the body with the forearm supported by the work surface. • Move the keyboard out of the way if necessary. • Avoid constant use without rest breaks. • Learn to use it with either hand. 39 Occupational Health & Safety Unit

40. Mouse and Trackball • Other issues: • Clogging – clean regularly, discard if bad. • Optical mice preferred as no clogging. • Cordless mice can be used when left and right handed people are using a workstation or if box located too far from monitor. • Scroll wheels can reduce the amount of ‘cut and paste’. 40 Occupational Health & Safety Unit

41. Laptop / Notebook Computers • These do not allow correct ergonomics due to the compact nature of the equipment. • Arm and neck position are less than ideal. • When using it for a long time it is better to plug laptop into regular screen and keyboard. • Can just use keyboard and mouse with screen raised to normal monitor height. • Use plug in mouse rather than touch pad. 41 Occupational Health & Safety Unit

42. Lighting issues • Glare: • Occurs when one part of an area is much brighter than the background or vice versa. • If a bright window is positioned behind a computer screen, the contrast and glare can be considerable. 42 Occupational Health & Safety Unit

43. To Reduce Glare • Control light through windows (blinds). • Reduce contrast between foreground and background. • Reposition workstation to reduce light falling on the work surface. • Reduce general lighting to suit the task. 43 Occupational Health & Safety Unit

44. Reflection Light reflected from a surface can make it difficult to see what is on it. To reduce reflections especially from computer screens, position screen side-on to main light source. 44 Occupational Health & Safety Unit

45. Screen Filters If repositioning doesn’t work, use screen filters. 45 Occupational Health & Safety Unit

46. Shadows • Shadows can encourage poor postures.To reduce: • Reposition work. • Redirecting lighting. • Install adjustable task lamp. • Remove barriers to light. 46 Occupational Health & Safety Unit

47. Posture Awkward posture can arise when people find it difficult to see what they are working with and they may lean closer to the object or bring it closer to their eyes. 47 Occupational Health & Safety Unit

48. Visual Rest Eye muscles can become tired when constantly focused on close work. To control visual tiredness, the person should focus on an object at a different distance to work that theyhave been looking at. This is a similar principle to taking rest breaks by varying tasks. 48 Occupational Health & Safety Unit

49. Assessing specific issues • When specific symptoms arise, it is necessary to: • Clarify the symptoms • Attempt to assess the cause of the symptoms when considering the ergonomics of the work and workstation. 49 Occupational Health & Safety Unit

50. Use of a checklist • The key issues are to determine: • Whether equipment is positioned correctly and is being used correctly. • Whether or not static muscle loading is occurring. • Whether or not aspects of the work are repetitive. An ergonomics checklist and other useful documentation can be obtained from the ‘toolbox’ on the OH&S web page. 50 Occupational Health & Safety Unit