| Twisting your hands puts
a strain on them. Resting on a wrist rest, the table, or arm
rests while typing forces you to twist your hand to reach some keys.
Instead, it is better to keep your hands moving freely above the keyboard,
letting the strong muscles of your arms move your hands. Rest your
wrists on a wrist rest only when you are NOT typing. Wrist rests
are designed to support the heel of your hand, not for resting your
wrists. Place wrist rests, so that the top is level with the
top of your keyboard's space bar.
Make sure you sit centered over the part of the keyboard
you use the most. Don't sit centered over the number pad if
you never use it.
There are a number of "ergonomic" keyboards
including one from Microsoft. Computers. Ergonomics is the study
of the interaction between the computer user and his/her environment.
While these keyboards can help reduce wrist or hand strain in some individuals,
the key to healthy hands has more to do with how you work, and how
often you take breaks rather than what type of keyboard you use.
Stretching your arm to reach out to the mouse can cause
mouse "shoulder" and "mouse arm". The mouse
should be placed near the keyboard so that it is easy to use without
stretching the arm too far away from the body.
Monitors
Looking at the monitor for extended periods can cause
eye strain. Eye strain means different things to different
people. It may be experienced as burning, tightness, sharp
pains, dull pains, watering, blurring, double vision, headaches, and other
sensations, depending on the person.
The major factors affecting the eye of a computer user
are glare, luminance, distance between the eye and screen, the user's
vision and his/her corrective lenses.
Keep the monitor as far away as you can to read comfortably.
Conventional wisdom for monitor height is that the top of the screen
should be at about eye level. This is fine for some people, but not quite
appropriate for others. The current recommendation is that
eye height is the highest a monitor should be at, not the best height.
Many people find a low monitor more comfortable for the eyes as well
as the neck.
Proper lighting for your work area is important. While you want
to be sure you can see your work, you also want to avoid looking
directly at a light source or having glare reflected off your screen.
Lighting should be indirect and even. Don't aim
a light at your reference documents, and be sure you're not facing
either a light or a window.
If possible, place your monitor at a 90 degree angle
to windows and other direct sources of light. A tiltable monitor
stand will enable you to adjust to different lights.
Keep your monitor screen clean, wipe it with a slightly
wet lint free cloth every day before you start work.
Set the brightness of your monitor at about the same
level as that of objects in your field of vision, such as the wall
in front of you. And keep reference documents at about the same distance
away from you as the screen for comfortable viewing.
The brightness and contrast control of the monitor should
be set properly for comfortable viewing. Turn the brightness
to minimum, then set the contrast to a level comfortable for your
viewing.
Natural mechanism of blinking gives our eyes micro rest.
Many people, when they view the computer monitor, the blinking rate
of their eyes goes down drastically, with little effort, this can
be corrected. For a few days, consciously try to blink at the
normal rate, if practiced for a week or two, you can regain your
natural blinking rate when using computers, this can reduce eye strain to
a good extent.
Seating
A well-designed chair will favorably affect posture,
circulation and the extent of strain on the spine. The chair should
allow you to place your feet firmly on the floor or a foot rest,
with your hips slightly flexed and your knees at a 60-90 degrees
angle. The seat should be comfortably wide, and the backrest about
six to nine inches high and 12 inches or more wide in the lumbar region.
Most chairs used by computer users has adjustments to
make it comfortable to sit on, but few people bother to adjust it.
Spending a little time learning how to adjust the chair and set it
correctly can go a long way in preventing back pain. With the
hips at 90 degrees. However, a great deal of recent research
supports the idea of a much wider hip angle -- with 130 degrees or
so as an "optimum" angle. The reason? When the hips are
straightened, the vertebrae of the lower spine are aligned with each
other in a way that reduces and evens out pressure on the intervertebral
discs. Further, sitting upright is less desirable than reclining.
When reclining, the lower back muscles work less and the spine supports
less weight, since body weight is held up by the chair's backrest.
Take a break!
Conventional practice recommends rest breaks about 15
minutes long, every two hours or so. This is insufficient for
work such as typing. Research supports the idea of very short
breaks done very frequently -- for example, 30-second breaks every 10
minutes or so. Taking a break can be as simple as taking your
hands off the keyboard and letting your arms droop at your sides.
These should happen in addition to the normal fifteen-minute coffee
breaks, when you should get up from your chair and do a few exercises to
loosen your neck and shoulder muscles.
Reduce glare to avoid eye strain
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Avoid light shining
directly into your eyes or onto your screen.
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Hold a mirror in
front of your screen to identify sources of glare.
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Avoid placing the
computer directly under a bank of lights.
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Lower lighting levels
to about half of the normal office lighting.
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Use task lighting
if necessary.
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Position the screen
at a right angle to the window.
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Use window curtains
or blinds if necessary.
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Safe Computing Tips
