Guidelines for arranging a Computer Workstation
Courtesy Cornell University Professor Alan Hedge
a good ergonomic working arrangement is important to protecting your health.
The following 10 tips are a brief summary of those things that most ergonomists
agree are important. If you follow the 10 tips they should help you to
improve your working arrangement. 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
tips for a good ergonomic workstation arrangement
through the following 10 steps to help you decide on what will be a good
ergonomic design for your situation:
will the computer be used? If it's 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 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. Also think about:
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 need to create an ergonomic arrangement.
kind of computer will be used? Ergonomic guidelines for computer
workstation arrangements assume that you will be using a desktop system
where the computer screen is separate from the keyboard. Laptops 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, or both
and a docking station.
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 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.
chair will be used? Choose a comfortable chair for the user to sit
in. If only one person is using this the chair can be at a fixed height
providing that it is comfortable to sit on and has a good backrest.
If more than one person will be using the computer, consider buying
and a chair with ergonomic features.
kind of work will the computer be used for? Try to anticipate what
type of software will be used most often.
processing - arranging the best keyboard/mouse position is high
the net, graphic design - arranging the best mouse position
is high priority.
entry- arranging the best numeric keypad/keyboard is a high
- arranging the best keyboard/mouse/game pad is a high priority.
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:
in front of the user and facing the user, not angled to the left
or right, to avoid 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.
should be centered 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 your 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.
should be placed at a height that doesn't make the user tilt their
head up to see it or bend their neck down to see it. When your 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. We see more
visual field below the horizon than above this, 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
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.
some instances and for some users, such as those who wear bifocal
corrective glasses, the monitor should be tilted backwards and the
height adjusted for comfortable screen viewing.
any adjustments feel uncomfortable then change them until the arrangement
feels more comfortable.
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:
the user's posture!
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).
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.
sure that they 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.
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.
sure the head and neck are as straight as possible .
sure the posture feels relaxed for the user.
sure that those things the user uses most frequently are placed
closest to the user so that they can be conveniently and comfortably
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).
sure that the phone is also close to you if you frequently use
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
will the computer be used? Think about the following environmental
conditions where the computer will be used.:
- 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
- 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 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.
a break! All ergonomists agree that it's a good idea to take frequent,
brief rest breaks: Practice the following:
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 form the eye surface.
- 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.
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.
breaks - there are many stretching and gentle exercises that
you can do to help relieve muscle fatigue. You should do these every
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. 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.
about ergonomic gizmos? These days just about everything is labeled
as being "ergonomically designed" and much of the time this
isn't true and these so-called ergonomic products can make things worse.
If you're thinking about buying an "ergonomic product" as
yourself the following 4 questions:
the product design and the manufacturer's claims make sense?
research evidence can the manufacturer provide to support their
claims? Be suspicious of products that haven't been studied by researchers.
it feel comfortable to use the product? If it doesn't then don't
do ergonomics experts say about the product? If they don't recommend
it don't use it.
There are many computer-related "ergonomic" products,
the most common ones being:
keyboards - most of these are keyboards where the alphanumeric
keys are split at an angle. For a non-touch typist this design can
be a disaster! The split design only addresses issues of hand ulnar
deviation, and research studies show that vertical hand posture
(wrist extension) is more important. There is no consistent research
evidence that most of the split-keyboard designs currently available
really produce any substantial postural benefits. For most people
a regular keyboard design works just fine if it's put in the proper
mouses - many of these mouse designs or alternative input device
designs can work well to improve your hand/wrist posture. However,
it's important to check that you can use these with your upper arm
relaxed and as close to your body as possible. Overreaching to an
"ergonomic mouse" defeats any benefits of this design.
rests - these were very popular a few years ago, but research
studies haven't demonstrated any substantial benefits for wrist
rests. If you choose to use a wrist rest a broad, flat surface design
works best. Avoid soft and squishy wrist rests because these will
contour to your wrist and encourage wrist-twisting movements. Your
hands should be able to glide over the surface of a wrist rest during
braces/gloves - There is no consistent research evidence that
wearing wrist supports during computer use actually helps reduce
the risk of injury. If you do like wearing a wrist support make
sure that it keeps your hand flat and straight, not bent upwards.
There is some evidence that wearing wrist supports at night in bed
can help relieve symptoms for those with carpal tunnel syndrome.
above 10 tips give a brief summary of good ergonomic design practice for
computer workstations, but there's lots more to consider. You can read
about ergonomics in many books, you can browse other materials on this
CUErgo web site, you can get information from the Human
Factors and Ergonomics Society, and you can ask expert ergonomists for
help and advice.
have any questions or comments about the information on this page or this
web site you can send these to Professor
Alan Hedge at Cornell University.
that all materials on this page and web site are copyright and may not
be copied or distributed without permission.
Alan Hedge, 2/6/99