Ergonomic Tips (06/01)
Keyboard and mouse ergonomics and safety
by John R. Chait D.C., drchait@home.com
Member of the Sarasota Personal Computer Users Group, Inc.
In the proper position, the keyboard should be placed just above the level of your lap. This is lower than most people normally place their keyboard, but lets your arms tilt downward while using the keyboard, leaving your elbows at a comfortable "open" angle. (If you don't have an adjustable keyboard tray, you may need to accomplish this by adjusting your chair height).
Using a slightly negative keyboard tilt will help you keep your
wrists in the proper (neutral) position. Try to avoid positive keyboard
tilt (i.e., where the top row of keys is noticeably higher than the
bottom row of keys). 
Also,
make sure that if there are "feet" attached to the bottom
front of your keyboard, they are left un-extended. Choose a system that
is height adjustable, this lets you tilt the keyboard away from you
slightly for better posture (negative tilt), and allows you to use the
mouse with your upper arms relaxed and as close to the body as possible.
Use you shoulder, not your wrist for all mouse motion.
If you use a keyboard tray, make sure there's enough room for your mouse. It should be close to your keyboard and on the same level, so that you don't have to reach far to grasp it. Also, if possible use an elbow pad for the arm that is using the mouse.
Split keyboards divide the keyboard into two halves, each of which points slightly outwards. The outward angle lets your wrists and forearms point inward without requiring your elbows to come in as far, better conforming to the contours of your body. Conversely, thinner people may find a traditional "straight" keyboard more comfortable.
Repeatedly bending your wrists up and down constricts the structures
inside the carpal tunnel in the wrist. This can cause pain and lead to injuries like carpal tunnel syndrome.
When you're typing, your forearms tend to sag as the arms tire, putting
the wrists into even greater wrist extension. If you are feeling any
symptoms that may be ergonomically related, be safe and get them checked
by a Chiropractor. :
Copyright 2001. This article is from the June 2001 issue of the Sarasota PC Monitor, the official monthly publication of the Sarasota Personal Computer Users Group, Inc., P.O. Box 15889, Sarasota, FL 34277-1889. Permission to reprint is granted only to other non-profit computer user groups, provided proper credit is given to the author and our publication. We would appreciate receiving a copy of the publication the reprint appears in, please send to above address, Attn: Editor. For further information about our group, email: admin@spcug.org/ Web: http://www.spcug.org/
The Sarasota Personal Computer Users Group, Inc. has 1,600+ members and was established in 1982. We are members of the Assoc. of PC User Groups (APCUG), the Florida Assoc. of PC Users Groups, Inc., and we are members of the America Online Ambassador Program.
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