Department of Occupational Safety and Health

1
Computer Workplace Ergonomics Awareness Training

• Department of Occupational Safety and Health
• Executive Vice Presidents Office
• Communications Workers of America, AFL-CIO

2
Overview

• Purpose of this course This course has been
  developed to assist the Unions leaders and
  members in the
• Identification and resolution of computer
  workplace ergonomic factors as well as related
  health hazards and member health problems

3
Overview

• Purpose of this course This course has been
  developed to assist the Unions leaders and
  members in the
• Identification and resolution of computer
  workplace ergonomic factors as well as related
  health hazards and member health problems
• Prevention of computer- related cumulative trauma
  or repetitive motion musculo-skeletal health
  symptoms and disorders.

4
Our Perspective

• CWA and its members have been in the forefront of
  experiencing and investigating the increased
  utilization of computers in the workplace.

5
Our Perspective

• CWA and its members have been in the forefront of
  experiencing and investigating the increased
  utilization of computers in the workplace.
• The number of CWA members using computers has
  increased steadily from 10,000 in 1979 to over
  450,000 today.

6
Our Perspective

• CWA and its members have been in the forefront of
  experiencing and investigating the increased
  utilization of computers in the workplace.
• The number of CWA members using computers has
  increased steadily from 10,000 in 1979 to over
  450,000 today.
• CWAs Occupational Safety and Health Department
  has been actively involved in preparing training
  and informational materials on health and safety
  hazards associated with workplace computer use as
  well as conducting training sessions, drafting
  collective bargaining language, and conducting
  and sponsoring scientific research regarding risk
  factors and controls.

7
Organization of This Program

• Organization of this program This program is
  divided into four (4) distinct but related
  components. Each session will focus on the injury
  and illness risk factors associated with each
  component and how you can reduce the risk of
  injury or illness to yourself and your
  co-workers. We begin this program with a brief
  overview of ergonomics.

8
Organization of this program

• Organization of this program This program is
  divided into four (4) distinct but related
  components. Each session will focus on the injury
  and illness risk factors associated with each
  component and how you can reduce the risk of
  injury or illness to yourself and your
  co-workers. We begin this program with a brief
  overview of ergonomics.
• The four(4) components of this awareness program
  are
• The visual environment
• Musculo-skeletal problems
• Occupational stress
• Reproductive hazards

9
What is Ergonomics?

• Ergonomics is the study of the relationship
  between human beings (workers), their work
  process, and the work environment.

Work process
Workers
Work environment
10
What is Ergonomics?

• Ergonomics is the study of the relationship
  between human beings (workers), their work
  process, and the work environment.
• Ergonomics means fitting the workplace to the
  physical, psychological and psychosocial (social
  relationship issues) characteristics of workers
  rather than having workers adapt to the design of
  workplace tools, equipment, and job tasks
• Ergonomics Fit the workplace to the
  worker
• Not
• the other way around

11
What is ergonomics?

• Ergonomics is the study of the relationship
  between human beings (workers), their work
  process, and work environment.
• Ergonomics means fitting the workplace to the
  physical, psychological and psychosocial
  characteristics of workers rather than having
  workers adapt to the design of workplace tools,
  equipment, and job tasks.
• Ergonomics,then, is a systematic approach to
  designing and creating work tools, equipment,
  work environments, and work organization that are
  safe, comfortable, and productive.

12
What is ergonomics?

• Ergonomics is the study of the relationship
  between human beings (workers), their work
  process, and work environment.
• Ergonomics means fitting the workplace to the
  physical, psychological and psychosocial
  characteristics of workers rather than having
  workers adapt to the design of workplace tools,
  equipment, and job tasks.
• Ergonomics, then, is a systematic approach to
  designing and creating work tools, equipment,
  work environments, and work organization that are
  safe, comfortable, and productive.
• Failure to consider ergonomics in the development
  of work tools, equipment, environments, and
  organizations often results in workers who suffer
  repetitive motion musculo-skeletal health
  symptoms and problems.

13
Computers and Vision Problems An Introduction

• Workers in computerized offices face at least
  four (4) potential visual problems

14
Computers and Vision Problems An Introduction

• Workers in computerized offices face at least
  four (4) potential visual problems
• Visual fatigue the eyes are overused without a
  break from viewing, or from environmental
  conditions such as glare which cause the eyes to
  focus too hard. A similar condition (temporary
  myopia--near-sightedness) happens when you read
  too much and for too long.

15
Computers and Vision Problems An Introduction

• Workers in computerized offices face at least
  four (4) potential visual problems
• Visual fatigue the eyes are overused without a
  break from viewing, or from environmental
  conditions such as glare which cause the eyes to
  focus too hard. A similar condition (temporary
  myopia--nearsightedness) happens when you read
  too much and for too long.
• Headaches These can occur from constant viewing
  without a break.

16
Computers and Vision Problems An Introduction

• Workers in computerized offices face at least
  four (4) potential visual problems
• Visual fatigue the eyes are overused without a
  break from viewing, or from environmental
  conditions such as glare which cause the eyes to
  focus too hard. A similar condition (temporary
  myopia--nearsightedness) happens when you read
  too much and for too long.
• Headaches These can occur from constant viewing
  without a break.
• Eye strain This results from overusing the eyes
  as well as from exposure to reflections and glare
  from the monitor, windows, and surrounding
  surfaces.

17
Computers and Vision Problems An Introduction

• Workers in computerized offices face at least
  four (4) potential visual problems
• Visual fatigue the eyes are overused without a
  break from viewing, or from environmental
  conditions such as glare which cause the eyes to
  focus too hard. A similar condition (temporary
  myopia--near-sightedness) happens when you read
  too much and for too long.
• Headaches These can occur from constant viewing
  without a break.
• Eye strain This results from overusing the eyes
  as well as from exposure to reflections and glare
  from the monitor, windows, and surrounding
  surfaces.
• Sore eyes This results from overusing the eyes
  as well as from exposure to reflections and glare
  from the monitor, windows, and surrounding
  surfaces.

18
Computers and Vision Problems An Introduction

• There is no evidence that these visual problems
  are permanent.

19
Computers and Vision Problems An Introduction

• There is no evidence that these visual problems
  are permanent.
• The National Academy of Sciences has
  characterized these visual problems as
  discomfort.

20
Computers and Vision Problems An Introduction

• There is no evidence that these visual problems
  are permanent.
• The National Academy of Sciences has
  characterized these visual problems as
  discomfort.
• These visual problems are usually temporary and
  often disappear after you leave work and have a
  chance to rest.

21
Computers and Vision Problems An Introduction

• There is no evidence that these visual problems
  are permanent.
• The National Academy of Sciences has
  characterized these visual problems as
  discomfort.
• These visual problems are usually temporary and
  often disappear after you leave work and have a
  chance to rest.
• They are more likely to happen in office jobs
  than in other kinds of work, except industrial
  quality control inspectors.

22
Computers and Vision Problems An Introduction

• Risk factors associated with these vision
  problems are
• Too much light (excess illumination)

23
Computers and Vision Problems An Introduction

• Risk factors associated with these vision
  problems are
• Too much light (excess illumination)
• Too little light (where hard copy is involved)

24
Computers and Vision Problems An Introduction

• Risk factors associated with these vision
  problems are
• Too much light (excess illumination)
• Too little light (where hard copy is involved)
• Glare from windows, computer screens, and shiny
  surfaces (e.g. walls, floors, glossy furniture)

25
Computers and Vision Problems An Introduction

• Risk factors associated with these vision
  problems are
• Too much light (excess illumination)
• Too little light (where hard copy is involved)
• Glare from windows, computer screens, and shiny
  surfaces (e.g. walls, floors, glossy furniture)
• Computer monitors, due to screen flickering and
  jitter, hard-to-read characters, and low contrast
  between characters and the background)

26
Computers and Vision Problems An Introduction

• Risk factors associated with these vision
  problems are
• Too much light (excess illumination)
• Too little light (where hard copy is involved)
• Glare from windows, computer screens, and shiny
  surfaces (e.g. walls, floors, glossy furniture)
• Computer monitors, due to screen flickering and
  jitter, hard-to-read characters, and low contrast
  between characters and the background) and
• Working too long without a break.

27
Computers and Vision Problems An Introduction

• Risk factors associated with these vision
  problems are
• Too much light (excess illumination)
• Too little light (where hard copy is involved)
• Glare from windows, computer screens, and shiny
  surfaces (e.g. walls, floors, glossy furniture)
• Computer monitors, due to screen flickering and
  jitter, hard-to-read characters, and low contrast
  between characters and the background) and
• Working too long without a break.
• Each of these risk factors is covered in more
  detail later on in this program.

28
Lighting

• Lighting has three basic properties that we are
  concerned with in the computerized office work
  environment
• Illumination the amount of light that falls on
  a given surface area

Light source
Surface area
29
Lighting

• Lighting has three basic properties that we are
  concerned with in the computerized office work
  environment
• Illumination the amount of light that falls on
  a given surface area
• Luminance or brightness the amount of light
  that reflects from a given surface area and

Surface area
30
Lighting

• Lighting has three basic properties that we are
  concerned with in the computerized office work
  environment
• Illumination the amount of light that falls on
  a given surface area
• Luminance or brightness the amount of light
  that reflects from a given surface area and
• Reflectance the ratio of luminance to
  illumination for a given surface area.

Reflectance () (Luminance ?Illumination) x 100
31
Lighting

• Reflectance () (Luminance ?Illumination x 100)

Light source
Low reflectance, because ratio of luminance
to illumination is relatively low.
Surface area
Light source
High reflectance, because most of luminance is
reflected back off the surface.
Surface area
32
Lighting

• Lighting has three basic properties that we are
  concerned with in the computerized office work
  environment
• Illumination the amount of light that falls on
  a given surface area
• Luminance or brightness the amount of light
  that reflects from a given surface area
• Reflectance the ratio of luminance to
  illumination for a given surface area.
• These basic properties should be used for
  designing computerized offices
• Flat, non- gloss finishes on walls and ceilings

33
Lighting

• Lighting has three basic properties that we are
  concerned with in the computerized office work
  environment
• Illumination the amount of light that falls on
  a given surface area
• Luminance or brightness the amount of light
  that reflects from a given surface area
• Reflectance the ratio of luminance to
  illumination for a given surface area.
• These basic properties should be used for
  designing computerized offices
• Flat, non- gloss finishes on walls and ceilings
• Floor coverings, even vinyl floors, should be a
  flat, non- gloss finish and

34
Lighting

• Lighting has three basic properties that we are
  concerned with in the computerized office work
  environment
• Illumination the amount of light that falls on
  a given surface area
• Luminance or brightness the amount of light
  that reflects from a given surface area and
• Reflectance the ratio of luminance to
  illumination for a given surface area.
• These basic properties should be used for
  designing computerized offices
• Flat, non- gloss finishes on walls and ceilings
• Floor coverings, even vinyl floors, should be a
  flat, non- gloss finish and
• Colors should be earth-tones, such as dark green
  or brown.

35
How much illumination do I need?

• A 1998 survey of CWA members found 55 of
  directory assistance operators, 52 of service
  representatives, and 43 of clerical computer
  operators said their workplace illumination
  seemed too bright or caused glare, making screen
  characters harder to read.

36
How much illumination do I need?

• A 1998 survey of CWA members found 55 of
  directory assistance operators, 52 of service
  representatives, and 43 of clerical computer
  operators said their workplace illumination
  seemed too bright or caused glare, making screen
  characters harder to read.
• The illumination required for a specific task is
  determined by matching the visual requirements of
  that particular task and the visual ability of
  the workers performing that task in other words,
  it is not one size fits all.

37
How much illumination do I need?

• A 1998 survey of CWA members found 55 of
  directory assistance operators, 52 of service
  representatives, and 43 of clerical computer
  operators said their workplace illumination
  seemed too bright or caused glare, making screen
  characters harder to read.
• The illumination required for a specific task is
  determined by matching the visual requirements of
  that particular task and the visual ability of
  the workers performing that task in other words,
  it is not one size fits all.
• The illumination levels in workplaces where
  computers are used should not be as high as
  workplaces where only hard copy is used. You
  probably want less light when you watch
  television and more light when youre reading the
  newspaper, since lower illumination levels
  improve the image quality on the screen and
  reduce screen glare.

38
How much illumination do I need?

• Problems occur when both computer screen and hard
  copy work is performed in the same work area.

39
How much illumination do I need?

• Problems occur when both computer screen and hard
  copy work is performed in the same work area.
• In these cases, a compromise is possible,
  achieved simply by lowering room lighting and
  providing individual task lighting at each work
  station as needed. This additional lighting needs
  to be carefully shielded and properly positioned
  to avoid glare and reflection on computer screens
  and other working surfaces used by nearby
  workers.

40
Glare

• Too much luminance (brightness) can produce
  glare, which may be produced in several different
  forms
• Glare from light sources (bulbs, luminaires,
  light fixtures) is called direct glare. Direct
  glare can be reduced by shielding the light
  sources with shades, baffles, louvers, or by
  recessed or indirect lighting. Indirect lighting
  in the photo below directs the light upwards.

41
Glare

• Too much luminance (brightness) can produce
  glare, which may be produced in several different
  forms
• Glare from light sources (bulbs, luminaires,
  light fixtures) is called direct glare. Direct
  glare can be reduced by shielding the light
  sources with shades, baffles, louvers, or by
  recessed or indirect lighting. An example of
  shielding is a lamp shade it reduces the direct
  glare but still provides adequate luminance.
• Glare from work surfaces (floors, tables, walls,
  ceilings) is reflected glare. Indirect glare can
  be reduced by changing the texture of these
  surfaces from glossy to flat or matte finishes
  and by changing the colors from bright to
  earth-tone colors. The eyes adapt and function
  more effectively when there is little difference
  between the luminance of the computer screen,
  work surface, and hard copy. The greater the
  difference in luminance, the more frequently and
  significantly your eyes have to adjust, resulting
  in visual fatigue.

42
Glare

• Controlling reflected glare from walls, floors,
  and work surfaces Generally, use treatments
  (textures, coverings, and colors) which absorb
  reflected glare. The reflectance ratio (the
  amount of luminance divided by the illumination
  falling on a given surface) for walls and floors
  effectively tells us how much of the illumination
  is absorbed.
• For walls, the recommended reflectance is 40-60

Illumination
Wall
Luminance
43
Glare

• Controlling reflected glare from walls, floors,
  and work surfaces Generally, use treatments
  (textures, coverings, and colors) which absorb
  reflected glare. The reflectance ratio (the
  amount of luminance divided by the illumination
  falling on a given surface) for walls and floors
  effectively tells us how much of the illumination
  is absorbed.
• For walls, the recommended reflectance is 40-60
• For work surfaces it is 25- 45

Light source
Surface area
44
Glare

• Controlling reflected glare from walls, floors,
  and work surfaces Generally, use treatments
  (textures, coverings, and colors) which absorb
  reflected glare. The reflectance ratio (the
  amount of luminance divided by the illumination
  falling on a given surface) for walls and floors
  effectively tells us how much of the illumination
  is absorbed.
• For walls, the recommended reflectance is 40-60
• For work surfaces it is 25- 45 and
• Floors should reflect the least amount.

45
Glare

• Controlling reflected glare from walls, floors,
  and work surfaces Generally, use treatments
  (textures, coverings, and colors) which absorb
  reflected glare. The reflectance ratio (the
  amount of luminance divided by the illumination
  falling on a given surface) for walls and floors
  effectively tells us how much of the illumination
  is absorbed.
• For walls, the recommended reflectance is 40-60
• For work surfaces it is 25- 45 and
• Floors should reflect the least amount.
• Controlling reflected glare from computer
  screens If possible, control glare at the
  source by shielding windows and overhead
  lighting. Anti- glare filters may be installed
  over the screen, but it may be necessary to try
  several different filters to find the right
  balance between glare reduction and character
  legibility and visibility.

46
Glare control a summary

• Direct glare from light sources (bulbs,
  luminaires, lighting bays and windows)-- use
  shades, luminaire covers or baffles, or
  recessed/indirect lighting.

47
Glare control a summary

• Direct glare from light sources (bulbs,
  luminaires, lighting bays and windows)-- use
  shades, luminaire covers or baffles, or
  recessed/indirect lighting.
• Reflected glare from walls, floors, work surfaces
  and the computer screen. Try to reduce the
  difference in luminance between all work surfaces
  and the monitor to minimize the adjustments your
  eyes have to make. Use treatments which absorb
  reflected glare, such as flat or matte finishes,
  as well as earth- tone colors instead of bright,
  high gloss colors, and use an anti- glare filter
  on the computer monitor if necessary. Even
  adjusting the monitor angle (vertical or
  horizontal) may help reduce reflected glare.

48
Computer Monitors

• CWAs 1998 member survey found 11 of directory
  assistance operators, ten percent of service
  representatives, and 12 of clerical computer
  operators had monitors which did not allow them
  to adjust the angle of the computer monitor.

49
Computer Monitors

• CWAs 1998 member survey found 11 of directory
  assistance operators, ten percent of service
  representatives, and 12, of clerical computer
  operators had monitors which did not allow them
  to adjust the angle of the computer monitor.
• Simply adjusting the vertical (up or down tilt)
  or horizontal (sideways) angle of the screen can
  help reduce screen reflections and reflected
  glare.

50
Computer Monitors

• CWAs 1998 member survey found 11 of directory
  assistance operators, ten percent of service
  representatives, and 12 of clerical computer
  operators had monitors which did not allow them
  to adjust the angle of the computer monitor.
• Simply adjusting the vertical (up or down tilt)
  or horizontal (sideways) angle of the screen can
  help reduce screen reflections and reflected
  glare.
• Screen reflections depend not only upon the
  screen tilt but also upon the operators viewing
  angle of the screen.

51
Computer Monitors

• CWAs 1998 member survey found 11 of directory
  assistance operators, ten percent of service
  representatives, and 12 of clerical computer
  operators had monitors which did not allow them
  to adjust the angle of the computer monitor.
• Simply adjusting the vertical (up or down tilt)
  or horizontal (sideways) angle of the screen can
  help reduce screen reflections and reflected
  glare.
• Screen reflections depend not only upon the
  screen tilt but also upon the operators viewing
  angle of the screen.
• Typically, visual angles should be within the
  range of 10- 20 degrees below horizontal.

52
Visual Problems Making things better, not worse

• Visual problems are often inter- related so are
  the fixes.

53
Visual Problems Making things better, not worse

• Visual problems are often inter- related so are
  the fixes.
• We can divide the problem into three separate
  parts
• Source of the problem
• Pathway (the way the problem travels towards the
  worker(s) and
• Receiver (the worker).

Pathway
Source
Receiver
54
Visual Problems Making things better, not worse

• Visual problems are often inter- related so are
  the fixes.
• We can divide the problem into three separate
  parts
• Source of the problem
• Pathway (the way the problem travels towards the
  worker(s) and
• Receiver (the worker).
• Applying this to the workplace,
• Source direct glare from the windows
• Pathway reflected glare from the walls, work
  surfaces, and computer screen and
• Receiver glare from work surfaces and screen.

55
Visual Problems Making things better, not worse

• We can divide the problem into three separate
  parts
• Source of the problem
• Pathway (the way the problem travels towards the
  worker(s) and
• Receiver (the worker).
• Applying this to the workplace,
• Source direct glare from the windows
• Pathway reflected glare from the walls, work
  surfaces, and computer screen and
• Receiver glare from work surfaces and screen.
• Applying the fixes
• Shades or curtains on the window(s) to control
  the source
• Wall and work surface treatments to absorb
  reflected glare and
• Anti- glare screen filter, tilted monitor, and
  more frequent rest breaks.

56
Visual Problems Making things better, not worse

• Control the lighting problem at the source
• Control light from windows by partly or totally
  closing or opening drapes, shades, or blinds,
  especially during sunny periods

57
Visual Problems Making things better, not worse

• Control the lighting problem at the source
• Control light from windows by partly or totally
  closing or opening drapes, shades, or blinds,
  especially during sunny periods
• Place computer screens parallel to windows and
  luminaires

58
Visual Problems Making things better, not worse

• Control the lighting problem at the source
• Control light from windows by partly or totally
  closing or opening drapes, shades, or blinds,
  especially during sunny periods
• Place computer screens parallel to windows and
  luminaires
• If possible, place computer monitors in between
  luminaires, not directly underneath them

59
Visual Problems Making things better, not worse

• Control the lighting problem at the source
• Control light from windows by partly or totally
  closing or opening drapes, shades, or blinds,
  especially during sunny periods
• Place computer screens parallel to windows and
  luminaires
• If possible, place computer monitors in between
  luminaires, not directly underneath them
• Use screen hoods to block excess lighting from
  overhead sources

60
Visual Problems Making things better, not worse

• Control the lighting problem at the source
• Control light from windows by partly or totally
  closing or opening drapes, shades, or blinds,
  especially during sunny periods
• Place computer screens parallel to windows and
  luminaires
• If possible, place computer monitors in between
  luminaires, not directly underneath them
• Use screen hoods to block excess lighting from
  overhead sources
• If possible, recess light fixtures and

61
Visual Problems Making things better, not worse

• Control the lighting problem at the source
• Control light from windows by partly or totally
  closing or opening drapes, shades, or blinds,
  especially during sunny periods
• Place computer screens parallel to windows and
  luminaires
• If possible, place computer monitors in between
  luminaires, not directly underneath them
• Use screen hoods to block excess lighting from
  overhead sources
• If possible, recess light fixtures and
• Use light-focusing diffusers. These look like
  lattice-work they direct most of the light
  directly downwards instead of trying to bounce it
  off the walls and floors.

62
Visual Problems Making things better, not worse
63
Visual Problems Making things better, not worse

• Control reflected glare on the pathway
• Reduce the amount of light reflected from walls,
  floors, and work surfaces using light absorbing
  colors and finishes. High- or semi- gloss
  finishes are not recommended matte finishes and
  soft earth tones are preferred. You may have to
  wait for remodeling, repainting, or the purchase
  of new furniture to implement these
  recommendations

64
Visual Problems Making things better, not worse

• Control reflected glare on the pathway
• Reduce the amount of light reflected from walls,
  floors, and work surfaces using light absorbing
  colors and finishes. High- or semi- gloss
  finishes are not recommended matte finishes and
  soft earth tones are preferred. You may have to
  wait for remodeling, repainting, or the purchase
  of new furniture to implement these
  recommendations
• Floors Reflectance ratio (amount of light
  reflected) should not exceed 30

Light source
Surface area
65
Visual Problems Making things better, not worse

• Control reflected glare on the pathway
• Reduce the amount of light reflected from walls,
  floors, and work surfaces using light absorbing
  colors and finishes. High- or semi- gloss
  finishes are not recommended matte finishes and
  soft earth tones are preferred. You may have to
  wait for remodeling, repainting, or the purchase
  of new furniture to implement these
  recommendations
• Floors Reflectance ratio (amount of light
  reflected) should not exceed 30 and
• Walls Reflectance ratio (amount of light
  reflected) should fall between 40- 60.

66
Visual Problems Making things better, not worse

• Control reflected glare on the pathway
• Reduce the amount of light reflected from walls,
  floors, and work surfaces using light absorbing
  colors and finishes. High- or semi- gloss
  finishes are not recommended matte finishes and
  soft earth tones are preferred. You may have to
  wait for remodeling, repainting, or the purchase
  of new furniture to implement these
  recommendations
• Floors Reflectance ratio (amount of light
  reflected) should not exceed 30
• Walls Reflectance ratio (amount of light
  reflected) should fall between 40- 60 and
• Work surfaces Reflectance ratio (amount of light
  reflected) should fall between 25- 45.

67
Visual Problems Making things better, not worse

• Control visual problems at the receiver
• Add anti- glare filters to the computer screen,
  provided they do not compromise character
  legibility and visibility

68
Visual Problems Making things better, not worse
69
Visual Problems Making things better, not worse

• Control visual problems at the receiver
• Add anti- glare filters to the computer screen,
  provided they do not compromise character
  legibility and visibility
• Tilt the screen up or down (vertical adjustment)
  or left-right (horizontal adjustment) to minimize
  glare and reflected images

70
Visual Problems Making things better, not worse

• Control visual problems at the receiver
• Add anti- glare filters to the computer screen,
  provided they do not compromise character
  legibility and visibility
• Tilt the screen up or down (vertical adjustment)
  or left-right (horizontal adjustment) to minimize
  glare and reflected images
• Adjust the brightness and contrast knobs of the
  computer monitor

71
Visual Problems Making things better, not worse

• Control visual problems at the receiver
• Add anti- glare filters to the computer screen,
  provided they do not compromise character
  legibility and visibility
• Tilt the screen up or down (vertical adjustment)
  or left-right (horizontal adjustment) to minimize
  glare and reflected images
• Adjust the brightness and contrast knobs of the
  computer monitor and
• Add more frequent rest breaks (micro-breaks).

72
Job Hazard Analysis Visual Problems
73
Computers and Musculoskeletal Problems An
Introduction

• Some of the temporary problems associated with
  computer work in offices includes
• Muscular fatigue
• Aches and pains in muscles and joints and
• Temporary weakness and dysfunction of muscles.

74
Computers and Musculoskeletal Problems An
Introduction

• Some of the temporary problems associated with
  computer work in offices includes
• Muscular fatigue
• Aches and pains in muscles and joints and
• Temporary weakness and dysfunction of muscles.
• However, there are some permanent disorders
  observed among those who perform computer work in
  offices including
• Lower back pain
• Cumulative trauma disorders of the upper
  extremities such as carpal tunnel syndrome and
  tendinitis
• Cervical- brachial disorder
• Thoracic outlet syndrome and
• Chronic fatigue.

75
Computers and Musculoskeletal Problems An
Introduction

• These permanent musculo- skeletal disorders occur
  at about the same rate among computer office
  workers as in other high- exposure industries,
  despite the fact that office work has always been
  thought of as safe work.

76
Computers and Musculoskeletal Problems An
Introduction

• These permanent musculo- skeletal disorders occur
  at about the same rate among computer office
  workers as in other high- exposure industries,
  despite the fact that office work has always been
  thought of as safe work.
• But when it comes to ergonomic hazards, office
  work is almost as dangerous as high risk
  manufacturing and other industries.

77
Computers and Musculoskeletal Problems An
Introduction

• Some of the temporary problems associated with
  computer work in offices includes
• Muscular fatigue
• Aches and pains in muscles and joints and
• Temporary weakness and dysfunction of muscles.

78
Computers and Musculoskeletal Problems An
Introduction

• Some of the temporary problems associated with
  computer work in offices includes
• Muscular fatigue
• Aches and pains in muscles and joints and
• Temporary weakness and dysfunction of muscles.
• However, there are some permanent disorders
  observed among those who perform computer work in
  offices including
• Lower back pain
• Cumulative trauma disorders of the upper
  extremities such as carpal tunnel syndrome and
  tendinitis
• Cervical- brachial disorder
• Thoracic outlet syndrome and
• Chronic fatigue.

79
Computers and Musculoskeletal Problems What
causes them?

• Ergonomics involves fitting the workplace to the
  worker. However, in many computer offices, the
  workstation isnt very flexible and the worker
  has to fit to the work station. The greater the
  lack of fit between the work station (as well as
  the work place) and the worker, the more
  significant the musculo-skeletal hazard.

Ergonomics Fit the workplace to the worker not
the other way around
80
Computers and Musculoskeletal Problems What
causes them?

• Ergonomics involves fitting the workplace to the
  worker. However, in many computer offices, the
  workstation isnt very flexible and the worker
  has to fit to the work station. The greater the
  lack of fit between the work station (as well as
  the work place), the more significant the
  musculo-skeletal hazard.
• Other risk factors include
• continuous work without adequate rest breaks

81
Computers and Musculoskeletal Problems What
causes them?

• Ergonomics involves fitting the workplace to the
  worker. However, in many computer offices, the
  workstation isnt very flexible and the worker
  has to fit to the work station. The greater the
  lack of fit between the work station (as well as
  the work place), the more significant the
  musculo-skeletal hazard.
• Other risk factors include
• continuous work without adequate rest breaks
• highly repetitive tasks (e.g. keyboarding) which
  take a very short period of time to complete

82
Computers and Musculoskeletal Problems What
causes them?

• Ergonomics involves fitting the workplace to the
  worker. However, in many computer offices, the
  workstation isnt very flexible and the worker
  has to fit to the work station. The greater the
  lack of fit between the work station (as well as
  the work place), the more significant the
  musculo-skeletal hazard.
• Other risk factors include
• continuous work without adequate rest breaks
• highly repetitive tasks (e.g. keyboarding) which
  take a very short period of time to complete
• using too much force because of excessive load or
  poor work methods and

83
Computers and Musculoskeletal Problems What
causes them?

• Ergonomics involves fitting the workplace to the
  worker. However, in many computer offices, the
  workstation isnt very flexible and the worker
  has to fit to the work station. The greater the
  lack of fit between the work station (as well as
  the work place), the more significant the
  musculo-skeletal hazard.
• Other risk factors include
• continuous work without adequate rest breaks
• highly repetitive tasks (e.g. keyboarding) which
  take a very short period of time to complete
• using too much force because of excessive load or
  poor work methods and
• continuous static loading of muscles (fixed
  postures) reduces circulation and increases the
  risk of musculoskeletal problems.

84
Computers and Musculoskeletal Problems What
causes them?

• Personal medical conditions and physical
  characteristics can increase the risk of
  cumulative trauma disorders, including
• circulatory problems
• obesity
• arthritis
• acute injuries to the bones, muscles, tendons,
  ligaments, or joints
• menopause and its treatment and
• pregnancy.

85
Computers and Musculoskeletal Problems Whats my
posture got to do with it?

• Operator complaints are most often related to
  pain in the neck, shoulders, back, and wrists.
  Less often mentioned is pain involving the arms,
  hands, and legs. Research indicates that these
  symptoms are reported more often by computer
  operators than in workers holding other jobs.

86
Computers and Musculoskeletal Problems Whats my
posture got to do with it?

• Operator complaints are most often related to
  pain in the neck, shoulders, back, and wrists.
  Less often mentioned is pain involving the arms,
  hands, and legs. Research indicates that these
  symptoms are reported more often by computer
  operators than in workers holding other jobs.
• The research literature indicates that serious
  musculoskeletal disorders are most often
  associated with computer jobs which require
  constrained working positions for the entire work
  shift.

87
Computers and Musculoskeletal Problems Whats my
posture got to do with it?

• Operator complaints are most often related to
  pain in the neck, shoulders, back, and wrists.
  Less often mentioned is pain involving the arms,
  hands, and legs. Research indicates that these
  symptoms are reported more often by computer
  operators than in workers holding other jobs.
• The research literature indicates that serious
  musculoskeletal disorders are most often
  associated with computer jobs which require
  constrained working positions for the entire work
  shift.
• While seated, the computer operator is subject to
  continuous stress on practically all postural
  muscles the amount of stress depends on the
  position of the parts of the workers body.

88
Computers and Musculoskeletal Problems Whats my
posture got to do with it?

• Leaning your head forward in a static position
  for extended periods, or to one side or the
  other, can lead to neck and shoulder fatigue and
  pain.

89
Computers and Musculoskeletal Problems Whats my
posture got to do with it?

• Leaning your head forward in a static position
  for extended periods, or to one side or the
  other, can lead to neck and shoulder fatigue and
  pain.
• Elevating your arms above their natural position
  will add to neck and shoulder strain over
  extended periods of time, this posture will make
  the condition worse.

90
Computers and Musculoskeletal Problems Whats my
posture got to do with it?

• Leaning your head forward in a static position
  for extended periods, or to one side or the
  other, can lead to neck and shoulder fatigue and
  pain.
• Elevating your arms above their natural position
  will add to neck and shoulder strain over
  extended periods of time, this posture will make
  the condition worse.
• Angling the wrists up or down outside their
  normal neutral position for extended periods of
  time is linked to tendinitis and carpal tunnel
  syndrome.

91
Computers and Musculoskeletal Problems Whats my
posture got to do with it?

• Leaning your head forward in a static position
  for extended periods, or to one side or the
  other, can lead to neck and shoulder fatigue and
  pain.
• Elevating your arms above their natural position
  will add to neck and shoulder strain over
  extended periods of time, this posture will make
  the condition worse.
• Angling the wrists up or down outside their
  normal neutral position for extended periods of
  time is linked to tendinitis and carpal tunnel
  syndrome.
• These postures are frequently necessary for
  computer operators to fit themselves to the
  configuration of equipment and the
  workstation.These are not natural positions.

92
Computers and Musculoskeletal Problems You mean
my job has risk factors?

• After many years of careful study, we have
  recognized there are several characteristics of
  computer jobs which are risk factors associated
  with musculoskeletal problems including
• the design of the equipment

93
Computers and Musculoskeletal Problems You mean
my job has risk factors?

• After many years of careful study, we have
  recognized there are several characteristics of
  computer jobs which are risk factors associated
  with musculoskeletal problems including
• the design of the equipment
• the work pace

94
Computers and Musculoskeletal Problems You mean
my job has risk factors?

• After many years of careful study, we have
  recognized there are several characteristics of
  computer jobs which are risk factors associated
  with musculoskeletal problems including
• the design of the equipment
• work pace
• repetitiveness of the job

95
Computers and Musculoskeletal Problems You mean
my job has risk factors?

• After many years of careful study, we have
  recognized there are several characteristics of
  computer jobs which are risk factors associated
  with musculoskeletal problems including
• the design of the equipment
• work pace
• repetitiveness of the job
• work and rest break schedules

96
Computers and Musculoskeletal Problems You mean
my job has risk factors?

• After many years of careful study, we have
  recognized there are several characteristics of
  computer jobs which are risk factors associated
  with musculoskeletal problems including
• the design of the equipment
• work pace
• repetitiveness of the job
• work and rest break schedules and
• personal attributes of workers.

97
Computers and Musculoskeletal Problems What
kinds of health problems are we talking about?

• At worst, many of these conditions can diminish
  your work capacity and lead to permanent
  disability. At the very least, they can require
  extensive and sometimes painful medical
  treatments.

98
Computers and Musculoskeletal Problems What
kinds of health problems are we talking about?

• At worst, many of these conditions can diminish
  your work capacity and lead to permanent
  disability. At the very least, they can require
  extensive and sometimes painful medical
  treatments.
• Carpal tunnel syndrome, which is becoming
  prevalent among keyboard operators, results in
  the loss of ability to carry out fine motor
  movements with the fingers or the ability to
  grasp and hold heavy objects.

99
Computers and Musculoskeletal Problems What
kinds of health problems are we talking about?

• At worst, many of these conditions can diminish
  your work capacity and lead to permanent
  disability. At the very least, they can require
  extensive and sometimes painful medical
  treatments.
• Carpal tunnel syndrome, which is becoming
  prevalent among keyboard operators, results in
  the loss of ability to carry out fine motor
  movements with the fingers or the ability to
  grasp and hold heavy objects.
• Specific risk factors for these repetitive motion
  injuries are
• high frequency of repetitive motion
• poor body- part posture, such as wrist flexion or
  extension
• high force requirements
• vibration and
• work organization.

100
Computers and Musculoskeletal Problems What can
I do about this?

• In the next series of slides, well focus on how
  you can reduce or eliminate these risk factors.
• Well focus on four main elements
• the keyboard/mouse
• the chair
• the workstation itself and
• rest breaks.

101
Computers and Musculoskeletal Problems What can
I do about this?
102
Keyboard and Mouse Design

• These two input devices by themselves arent
  dangerous, but the way they are used in relation
  to posture and other workstation components can
  increase or decrease the risk of repetitive
  motion illness.

103
Keyboard and Mouse Design

• These two input devices by themselves arent
  dangerous, but they way they are used in relation
  to posture and other workstation components can
  increase or decrease the risk of repetitive
  motion illness.
• The keyboard and the mouse need to be detachable
  and moveable so they can be positioned to best
  suit the posture and work requirements of the
  computer operator.

104
Keyboard and Mouse Design

• These two input devices by themselves arent
  dangerous, but they way they are used in relation
  to posture and other workstation components can
  increase or decrease the risk of repetitive
  motion illness.
• The keyboard and the mouse need to be detachable
  and moveable so they can be positioned to best
  suit the posture and work requirements of the
  computer operator.
• The keyboard angle should be relatively flat and
  adjustable, particularly when several different
  operators may use the same keyboard

105
Keyboard and Mouse Design

• These two input devices by themselves arent
  dangerous, but they way they are used in relation
  to posture and other workstation components can
  increase or decrease the risk of repetitive
  motion illness.
• The keyboard and the mouse need to be detachable
  and moveable so they can be positioned to best
  suit the posture and work requirements of the
  computer operator.
• The keyboard angle should be relatively flat and
  adjustable, particularly when several different
  operators may use the same keyboard.
• You should try to adjust your keyboard angle to
  keep your wrist as flat (neutral) as possible.
  Sometimes you can do this by moving the keyboard
  farther away from you, or turning the keyboard
  over and adjusting the angle tabs.

106
Mouse Design

• The mouse should be designed to fit comfortably
  into your hand with click buttons position level
  with the keyboard. If you are left-handed, use a
  left-handed or ambidextrous mouse.

107
Mouse Design

• The mouse should be designed to fit comfortably
  into your hand with click buttons position level
  with the keyboard. If you are left-handed, use a
  left-handed or ambidextrous mouse.
• The mouse should be at the same height and angle
  as the keyboard and situated next to the keyboard.

108
Mouse Design

• The mouse should be designed to fit comfortably
  into your hand with click buttons position level
  with the keyboard. If you are left-handed, use a
  left-handed or ambidextrous mouse.
• The mouse should be at the same height and angle
  as the keyboard and situated next to the
  keyboard.
• The surface upon which the mouse is used should
  be large enough to allow adequate movement and
  proper operation.

109
Mouse Design

• The mouse should be designed to fit comfortably
  into your hand with click buttons position level
  with the keyboard. If you are left-handed, use a
  left-handed or ambidextrous mouse.
• The mouse should be at the same height and angle
  as the keyboard and situated next to the
  keyboard.
• The surface upon which the mouse is used should
  be large enough to allow adequate movement and
  proper operation.
• When using the mouse, it should be held loosely
  with the wrist in a neutral position, operated by
  moving the entire arm and shoulder.
• In order to minimize arm and wrist movement,
  adjust the mouse software program to control the
  mouse speed and sensitivity.

110
Mouse Design

• The mouse should be designed to fit comfortably
  into your hand with click buttons position level
  with the keyboard. If you are left-handed, use a
  left-handed or ambidextrous mouse.
• The mouse should be at the same height and angle
  as the keyboard and situated next to the
  keyboard.
• The surface upon which the mouse is used should
  be large enough to allow adequate movement and
  proper operation.
• When using the mouse, it should be held loosely
  with the wrist in a neutral position, operated by
  moving the entire arm and shoulder.
• In order to minimize arm and wrist movement,
  adjust the mouse software program to control the
  mouse speed and sensitivity.
• A light touch should be used when clicking the
  mouse buttons. Periodically remove your hand
  from the mouse.

• In order to minimize arm and wrist movement,
  adjust the mouse software program to control the
  mouse speed and sensitivity.

111
Wrist rests

• Wrist rests are another way to reduce static
  loading and maintain a neutral wrist. They can
  also avoid your wrist resting on the sharp edge
  of the desk, which can adversely affect your
  blood supply and nerves going into your hand.
  (Its only natural that youll want to rest your
  elbows, arms, and/or wrists on something solid to
  relieve the static loading and fatigue of holding
  your lower arms outstretched for extended time
  periods).

Wrist rests
112
Wrist rests

• Wrist rests are another way to reduce static
  loading and maintain a neutral wrist. They can
  also avoid your wrist resting on the sharp edge
  of the desk, which can adversely affect your
  blood supply and nerves going into your hand.
  (Its only natural that youll want to rest your
  elbows, arms, and/or wrists on something solid to
  relieve the static loading and fatigue of holding
  your lower arms outstretched for extended time
  periods).
• Be careful what you rest your wrist on! Wrist
  rests should be at least two inches wide and
  should be placed over some edges, such as the
  edge of the keyboard surface or the work
  table.They should also be padded and provide some
  support.

113
Wrist rests

• Wrist rests are another way to reduce static
  loading and maintain a neutral wrist. They can
  also avoid your wrist resting on the sharp edge
  of the desk, which can adversely affect your
  blood supply and nerves going into your hand.
  (Its only natural that youll want to rest your
  elbows, arms, and/or wrists on something solid to
  relieve the static loading and fatigue of holding
  your lower arms outstretched for extended time
  periods).
• Be careful what you rest your wrist on! Wrist
  rests should be at least two inches wide and
  should be placed over some edges, such as the
  edge of the keyboard surface or the work
  table.They should also be padded and provide some
  support.
• Wrist rests should be used when resting, not
  while keyboarding or using the mouse.

114
The Chair

• Our 1998 CWA survey found that four per cent of
  directory assistance operators, 11 of service
  representatives, and 15 of clerical computer
  operators did not have an adjustable chair. The
  chair is a critical component of an
  ergonomically- correct computer workstation.

115
The Chair

• Our 1998 CWA survey found that four per cent of
  directory assistance operators, 11 of service
  representatives, and 15 of clerical computer
  operators did not have an adjustable chair.
• The chair needs to be adjustable in terms of
• the height of the seat pan (up or down)
• the angle of the seat pan (forward or backward
  tilt)
• the backrest (up or down, tension) and
• the distance to or from the work being done.

116
The Chair
117
The Chair

• Our 1998 CWA survey found 4 of directory
  assistance operators, 11 of service
  representatives, and 15 of clerical computer
  operators did not have an adjustable chair.
• The chair needs to be adjustable in terms of
• the height of the seat pan (up or down)
• the angle of the seat pan (forward or backward
  tilt)
• the backrest (up or down, tension) and
• the distance to or from the work being done.
• Having these adjustable features allows you to
  find your own personal comfort zone, where your
  feet are comfortably supported on the floor on a
  proper foot rest, your wrists are flat and as
  neutral as possible, and you have proper support
  from your chair with some wiggle room.

118
The Chair and the Zone

• How do you find your own comfort zone?
• If you have to bend your wrists down (wrist
  flexion) to use the keyboard, youre probably
  sitting too low and you need to raise your chair
  and/or lower your keyboarding surface.

119
The Chair and the Zone

• How do you find your own comfort zone?
• If you have to bend your wrists down (wrist
  flexion) to use the keyboard, youre probably
  sitting too low and you need to raise your chair
  and/or lower your keyboarding surface.
• If you have to bend your wrists up (wrist
  extension) to use the keyboard, youre probably
  sitting too high and you need to lower your chair
  and/or raise your keyboarding surface.

120
The Chair and the Zone

• How do you find your own comfort zone?
• If you have to bend your wrists down (wrist
  flexion) to use the keyboard, youre probably
  sitting too low and you need to raise your chair
  and/or lower your keyboarding surface.
• If you have to bend your wrists up (wrist
  extension) to use the keyboard, youre probably
  sitting too high and you need to lower your chair
  and/or raise your keyboarding surface.
• The seat pan height should be adjustable from a
  low of 16 inches to a high of 20 inches from the
  top of the seat pan to the floor.

121
The Chair and the Zone

• How do you find your own comfort zone?
• If you have to bend your wrists down