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You Are Here: Home > Learn More > Ergonomic Tips > Planning and Creating an Ergonomic Computer Workstation, in 10 Steps, and How to Take a Break
Ergonomic Tips for Computer Workstations - 10 Steps for Users
Alan Hedge,
Ph.D., FErgS, AFBPsS
Professor, Ergonomics
Cornell University
Ithaca, NY, USA
Creating a good ergonomic working arrangement is important to protecting your
health. The following 10 steps are a brief summary of those things that most
Ergonomists agree are important. If you follow the 10 steps they should help you
to improve your working arrangement. You can also use the Computer Workstation
Checklist to help to pinpoint any areas of concern and take a look at the
'Computer Workstation summary' diagram' for specific tips. However, every
situation is different, and if you can't seem to get your arrangement to feel
right or you are confused about some of the following recommendations you should
seek professional advice.
10 steps for a good ergonomic workstation arrangement
Work through the following 10 steps to help you decide on what will be a good
ergonomic design for your situation:
1. How will the computer be used?
- who will be using the computer? If the computer will only be used
by one person then the arrangement can be optimized for that person's size
and shape, and features such as an adjustable height chair may be
unnecessary. If it's going to be used by several people, you will need to
create an arrangement that most closely satisfies the needs of the extremes,
that is the smallest and tallest, thinnest and broadest persons, as well as
those in between these extremes. (See our selection of computer
monitor arms)
- how long will people be using the computer? If it's a few minutes a
day then ergonomic issues may not be a high priority. If it's more than 1
hour per day you should create an ergonomic arrangement. If it's more than 4
hours then you should consider implementing an ergonomic arrangement.
2. What kind of computer will be used?
- Desktops - Most ergonomic guidelines for computer workstation
arrangements assume that you will be using a desktop system where the
computer screen is separate from the keyboard.
- Laptop computers are growing in popularity and are great for short
periods of computer work. Guidelines for laptop use are more difficult
because laptop design inherently is problematic - when the screen is at a
comfortable height and distance the keyboard isn't and vice versa. For
sustained use you should consider purchasing either:
- - an external monitor
- an external keyboard, preferably with a negative-tilt keyboard tray
- both, and
- a docking station and then arranging your workspace to create a good
workstation layout.
3. What furniture will you use?
Make sure that the computer (monitor, CPU system unit, keyboard, mouse) are
placed on a stable working surface (nothing that wobbles) with adequate room for
proper arrangement. If this work surface is going to be used for writing on
paper as well as computer use a flat surface that is between 28"-30"
above the floor (suitable for most adults). You should consider attaching a
keyboard/mouse tray system to your work surface. Choose a system that is
height adjustable, that allows you to tilt the keyboard down away from you
slightly for better wrist posture (negative tilt), and that allows you to use
the mouse with your upper arms relaxed and as close to the body as possible and
with your wrist in a comfortable and neutral position.
4. What chair will be used?
Choose a comfortable chair for the user to sit in. If only one person is
using this the chair can even be at a fixed height providing that it is
comfortable to sit on and has a good backrest that provides lumbar
support. If
more than one person will be using the computer, consider buying and a chair
with several ergonomic features. Studies show that the best seated posture is a
reclined posture of 100-110 degrees NOT the upright 90 degree posture that is
often portrayed. In the recommended posture the chair starts to work for the
body and there are significant decreases in postural muscle activity and in
intervetebral disc pressure in the lumbar spine. Erect sitting is NOT relaxed,
sustainable sitting, reclined sitting is.
5. What kind of work will the computer be used for?
Try to anticipate what type of software will be used most often.
- Word processing - arranging the best keyboard/mouse position is high
priority.
- Surfing the net, graphic design - arranging the best mouse position is
high priority.
- Data entry- arranging the best numeric keypad/keyboard is a high priority.
- Games - arranging the best keyboard/mouse/game pad is a high priority.
6. What can you see?
Make sure that any paper documents that you are reading are placed as close
to the computer monitor as possible and that these are at a similar angle - use
a document holder where possible.
The computer monitor should be placed:
- directly in front of you and facing you, not angled to the left or
right. This helps to eliminate too much neck twisting. Also, whatever the
user is working with, encourage him/her to use the screen scroll bars to
ensure that what is being viewed most is in the center of the monitor rather
than at the top or bottom of the screen.
- center the monitor on the user so that the body and/or neck isn't
twisted when looking at the screen. However, if you are working with a large
monitor and spend most of your time working with software like MSWord, which
defaults to creating left aligned new pages, and you don't want to have to
drag these to more central locations, try aligning yourself to a point about
1/3rd of the distance across the monitor from the left side.
- put the monitor at a comfortable height that doesn't make the user
tilt their head up to see it or bend their neck down to see it. When you are
seated comfortably, a user's eyes should be in line with a point on the
screen about 2-3" below the top of the monitor casing. We actually see
more visual field below the horizon than above this (look down a corridor
and you'll see more of the floor than the ceiling), so at this position the
user should comfortably be able to see more of the screen. If the monitor is
too low, the user will crane their neck forwards, if it's too high they'll
tilt their head backwards and end up with neck/shoulder pain.
- bifocals and progressive lens - even if you wear bifocals or
progressive lens, if you sit back in your chair in a reclined posture (with
you back at around 110 degrees) that is recommended for good low back
health, rather than sitting erect at 90 degrees, and if you slightly tilt
the monitor backwards and place this at a comfortable height you should be
able to see the screen without tilting your head back or craning your neck
forwards. Postural problems with bifocals can occur if you sits erect or
even hunched forwards. The problem with low monitors is that they cause neck
flexion and suffer more from glare. Recent studies have shown that the best
position for a computer monitor is for the center of the screen to be at
around 17.5 degrees below eye level. Try to align your eyes with the top of
the viewing area of the screen, and this should put the center about right
geometrically.
- viewing distance - the monitor should be at a comfortable
horizontal distance for viewing, which usually is around an arms length (sit
back in your chair and raise your arm and your fingers should touch the
screen). At this distance you should be able to see the viewing area of the
monitor without making head movements. If text looks too small then either
use a larger font or magnify the screen image in the software rather than
sitting closer to the monitor.
- screen quality - use a good quality computer screen. Make sure that
the text characters on your screen look sharp, and that they are a
comfortable size (you can change the screen resolution to find a comfortable
and clear character size). If you can see the screen flickering out of the
corner of your eye you should try increasing the refresh rate of your
monitor (with a PC you can change monitor resolution and refresh rates using
the Monitor control panel in your Settings folder, with a Mac you can use
the Monitor control panel). You can also consider using a good quality glass
anti-glare filter or an LCD display (like a laptop screen).
- eye checkup - there are natural changes in vision that occur in
most people during their early 0's. It's a good idea to periodically have
your eyes checked by a qualified professional. If any screen adjustments
feel uncomfortable then change them until the arrangement feels more
comfortable or seek further professional help.
7. Posture, posture posture!
Good posture is the basis of good workstation ergonomics. Good posture is the
best way to avoid a computer-related injury. To ensure good user posture:
Watch the user's posture!
- Make sure that the user can reach the keyboard keys with their wrists as
flat as possible (not bent up or down) and straight (not bent left or
right).
- Make sure that the user's elbow angle (the angle between the inner surface
of the upper arm and the forearm) is at or greater than 90 degrees to avoid
nerve compression at the elbow.
- Make sure that the upper arm and elbow are as close to the body and as
relaxed as possible for mouse use - avoid overreaching. Also make sure that
the wrist is as straight as possible when the mouse is being used.
- Make sure the user sits back in the chair and has good back support. Also
check that the feet can be placed flat on the floor or on a footrest.
- Make sure the head and neck are as straight as possible .
- Make sure the posture feels relaxed for the user.
8. Keep it close!
- Make sure that those things the user uses most frequently are placed
closest to the user so that they can be conveniently and comfortably
reached.
- Make sure that the user is centered on the alphanumeric keyboard. Most
modern keyboards are asymmetrical in design (the alphanumeric keyboard is to
the left and a numeric keypad to the right). If the outer edges of the
keyboard are used as landmarks for centering the keyboard and monitor, the
users hands will be deviated because the alphanumeric keys will be to the
left of the user's midline. Move the keyboard so that the center of the
alphanumeric keys (the B key, is centered on the mid-line of the user).
- Make sure that the phone is also close to you if you frequently use it.
9. A good workstation ergonomic arrangement will allow any computer
user to work in a neutral, relaxed, ideal typing posture that will minimize the
risk of developing any injury. An ideal keyboard arrangement is to place this on
a height adjustable negative-tilt tray. An ideal mouse arrangement is for this
to be on a flat surface that's 1-2" above the keyboard and moveable over
the numeric keypad. If you want a surface at the level of the keyboard base then
make sure that this can also be angled downwards slightly to help to keep your
hands in wrist neutral while you are mousing, and keep your elbow is as close to
the body as possible while you work.
10. Where will the computer be used?
Think about the following environmental conditions where the computer will be
used:
- Lighting - make sure that the lighting isn't too bright. You
shouldn't see any bright light glare on the computer screen. If you do, move
the screen, lower the light level, use a good quality, glass anti-glare
screen. Also make sure that the computer monitor screen isn't backed to a
bright window or facing a bright window so that there's the screen looks
washed out (use a shade or drapes to control window brightness).
- Ventilation - make sure that you use your computer somewhere that
has adequate fresh-air ventilation and that has adequate heating or cooling
so that you feel comfortable when you're working.
- Noise - noise can cause stress and that tenses your muscles which
can increase injury risks. Try to choose a quiet place for your workstation,
and use low volume music, preferably light classical, to mask the hum of any
fans or other sound sources.
Take a break! All Ergonomists agree that it's a good idea to take
frequent, brief rest breaks: Practice the following:
- Eye breaks - looking at a computer screen for a while causes some
changes in how the eyes work, causes you to blink less often, and exposes
more of the eye surface to the air. Every 15 minutes you should briefly look
away from the screen for a minute or two to a more distant scene, preferably
something more that 20 feet away. This lets the muscles inside the eye
relax. Also, blink your eyes rapidly for a few seconds. This refreshes the
tear film and clears dust from the eye surface.
- Micro-breaks - most typing is done in bursts rather than
continuously. Between these bursts of activity you should rest your hands in
a relaxed, flat, straight posture. During a micro-break (< 2minutes) you
can briefly stretch, stand up, move around, or do a different work task e.g.
make a phone call). A micro-break isn't necessarily a break from work, but
it's a break from the use of a particular set of muscles that's doing most
of the work (e.g. the finger flexors if you're doing a lot of typing).
- Rest breaks - every 30 to 60 minutes you should take a brief rest
break. During this break stand up, move around and do something else. Go and
get a drink of water, soda, tea, coffee or whatever. This allows you to rest
and exercise different muscles and you'll feel less tired.
- Exercise breaks - there are many stretching and gentle exercises
that you can do to help relieve muscle fatigue. You should do these every
1-2 hours.
- Ergonomic software - working at a computer can be hypnotic, and
often you don't realize how long you've been working and how much you've
been typing and mousing. You can get excellent ergonomic software that you
can install on your computer (free download available at
http://www.magnitude.com). The best software will run in the background
and it will monitor how much you've been using the computer. It will prompt
you to take a rest break at appropriate intervals, and it will suggest
simple exercises.
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