Computer Ergonomics



The following topics are of interest to computerists and people who do a lot of desk-work:



Having comfortable and attractive furniture will have an immediate and noticeable effect. Most importantly, years later, you are less likely to have troubles related to spending many hours sitting in a incorrectly designed chair.

The Chair

Your chair will be your most important piece of office equipment. So, make your purchase carefully. Shop around and ask a lot of questions. Be sure you don't have to be an acrobat to adjust the darn thing! See that it has all the features you need. It should have an adjustable seat pan. Adjust it so that it angles slightly down. This will keep pressure off of the lower back. For people working with keyboards for extended time periods, it's best to angle the seat down in front. Arm rests should be adjustable and removable. The chair should swivel and move. It is important that it has lumbar (lower back) support. The seat height and the backrest need to be adjustable. These should also be laterally adjustable.

While sitting in your brand new fancy chair, check your posture now and then. Make sure the lower back is firmly against the chair back. All the main blood vessels that supply the extremities run down the back of the legs. Therefore, crossing your legs greatly decreases the blood flow to your heart and puts an unnecessary strain on it. So - keep your feet flat on the floor. If you can't reach, use a foot rest.

Palms should be kept up off the keyboard. Use wrist rests. Position your tilting keyboard pan so your elbows are bent at 90 degree angles and your wrists at 10 to 20 degrees from horizontal. The middle row of the keyboard should be at elbow level. Also, hit the keys as lightly as possible. It doesn't require great force to depress a computer key.

Be certain your office and desk lighting is correct. If not, change it, if possible. Bad lighting can cause irritating glare. Anti-glare filters that fit over your VDT screen, indirect lighting, non-reflecting glass screens can prevent glare and minimize eyestrain. Remind yourself to blink frequently to keep your eyes moist and comfortable while computing and reading. Eye strain is a common computer user's discomfort. To help prevent it, say to yourself, "I am now relaxing my eyes." say anything that will help you to not stare the computer down!

Instead of laying papers flat, use a document holder next to the screen. Keep your neck as relaxed as possible, your chin slightly down and tucked in, your head straight ahead. If you do much copying, you might consider learning touch typing so that you can remain focused on the copy, and not have to switch back and forth from copy to keyboard, to monitor. If you are involved in graphics, don't strangle your mouse. You'll have as much accuracy when you hold it lightly.

The Desk

Get yourself a desk which allows you to sit at least 24 inches away from your monitor. There should be room for a wrist pad between the edge of the desk and the keyboard. The monitor should be positioned 15 to 30 degrees lower than your eyes. Interestingly, many so-called "computer desks" are ergonomic disaster areas. With these desks, the monitor is too high for a comfortable neck, too close for comfortable eyes, and there is no room for your papers, books, notes and disks.

If you have a large desktop, try to avoid the common habit of pushing the keyboard forward and then slouching over to reach it. Otherwise, you may look like a C-clamp in a few years.

More important than the furniture is your workplace's emotional atmosphere, of course. If it's not satisfactory, do what you can along with your boss and co-workers to change it. You and everyone involved will be happier and healthier for it, and the company will also profit from your greater productivity.

Cumulative Trauma Disorders

Computing can also be a strain on your eyes, especially if you have contacts. Excessive hours in front of your computer can also cause eye irritation, blurred vision, discomfort in your neck, back, shoulders, joint pain, and other symptoms discussed in the previous chapter. Sitting is one of the most structurally taxing "activities" for your neck and back. Slouching compounds the discomforts long-time sitting can cause. It compresses the spinal nerves, unduly stresses the spine, causes muscle tension, headache strain, and fatigue, which can in turn cause unclear thinking.

Have someone who knows about posture show you how to sit. Lazy posture and incorrect body mechanics while word processing, probably causes more muscle and joint pain and problems than anything else.

Just four hours a week at a computer is sufficient time to cause a significant injury if you are working at a inefficiently designed or adjusted workstation. With the old-time typewriters, there were frequent arm and wrist position changes and natural breaks, like putting in new paper and carriage returns. Today, it's non-stop and high-speed; which puts more wear and tear on hands and wrists because there is no recovery time. We aren't physically equipped to handle thousands of repetitive motions an hour. The most common injury is Carpal Tunnel Syndrome. Carpal Tunnel Syndrome is a compression of a nerve which runs through your wrist, resulting in a tingling sensation in your fingers or pain in fingers, hands or wrists.

Women run a two to five times greater risk of suffering from CTD (Cumulative Trauma Disorders, which includes carpal tunnel syndrome) than men. The incidences of this injury have reached alarming proportions.

"Cumulative Trauma Disorders have become the nation's leading cause of occupational illnesses." says Sharon Danann, research director of Nine-To-Five, the National Association of Working Women. And in the 1990's, they will account for one-half of all job related disorders."

Approximately a fifth of the LA Times' editorial staff have had CTD symptoms. Not just computer-workers are at risk. Anyone who uses their hands in a repetitive way for long periods of time are. Retail and grocery clerks, mail workers, gardeners, musicians, and assembly-line people all have CTD complaints.

NOTE: Use your entire hand while picking things up, not just the thumb and forefinger. This takes the stress off of the wrist.

Monitors and Electromagnetic Fields

Monitors emit several kinds of radiation. Ultraviolet light radiation has been blamed for cataracts, and high and low frequency electromagnetic radiations have been blamed for cancers and birth defects. So far, it hasn't been proven or disproven that any of these radiations around computers actually cause biological damage. The radiations your VDT emits are said to be in the "safe" range. Still, "buyer be ware." For safety's sake, put your monitor at least 24 inches away from your body. The electromagnetic radiation* is very strong close to the tube, but fades rapidly as you move further away. At three feet, the radiation is indistinguishable from natural background radiation (with today's detection instruments). Directly in front of a monitor is a safer place than to the side or behind, because there is a high-voltage coil in the back or one side which is the highest emitter of electromagnetic radiation. So - do not get close to the back or the sides of the monitor, even if it's in the next room. This type of radiation penetrates walls.

*Studies suggest that it's wise to avoid this radiation by not sleeping or sitting for a long time near electric devices; by unplugging water bed heaters and electric blankets before going to bed, and by staying at least 5 feet away from all sides of your T.V.

For light radiation, anti-radiation screens can help, but only block electric fields at very low frequency levels and extremely low frequency levels (VLF and ELF). They do not block magnetic fields, and high frequencies, which are thought by many scientists to be a more serious danger.

Below are some of the health problems that have been linked to extensive computer use:

Pregnancy Disorders

A possible increased risk of miscarriage or birth defects. Radiation and on-the-job emotional and physical stress has been suggested to be a possible explanation for this. Very controlled studies have not yet confirmed the connection.


Ultraviolet radiation from your computer screen has NOT been found to cause them. The levels known to cause cataracts are 10,000 times higher than those coming from a VDT.

NOTE: For more information on the exposure hazards of magnetic fields, read Paul Brodeau's CURRENTS OF DEATH. To gain more knowledge of your electromagnetic field, read Robert O. Becker's THE BODY ELECTRIC.

Computer Related Injury Prevention

According to numerous sources and research, the best prevention technique is to simply take frequent breaks - more about this in a few seconds. Since there's no time for long workouts on the job, look for hidden exercise opportunities. Take a brisk 10 minute walk during lunch, do some deep breathing or just stand up by your desk and do some simple stretches. These short spurts of exercise taken throughout the day will help with weight loss and lowered heart rates. And of course, remember to use the stairs instead of the elevator. During your rest periods, it is extremely important to relax your hands. Let them go limp, shake them out, massage them, anything but bending, twisting or straining your wrists or fingers. To help maintain healthy eyesight, look as far into the distance as possible for 15 seconds, many times a day.

You will produce more if you break at least once every 45 minutes. Although, ideally, the "20/20" approach is best. This means that every 20 minutes, you would get up and stretch, and/or move around for 20 seconds. An old-fashioned oven timer works well for this. Or you can set your digital watch or clock to go off at regular intervals. Also, there are some TSR programs containing timer alarms that will interrupt your work to let you know it's time to rest and stretch.

And, remember to breathe deeply in a natural manner. Be sure that there is adequate ventilation in your workplace so you can.

Relaxation and Stretching

For those of you who are overwhelmed - take heart. As with the information on injury prevention, choose only what you have the time and inclination for. Even if you choose just one or two hints and exercises from each segment - the relief you will feel will have made it far worth the effort!

Every five minutes, look across your office or out the window. On those conference calls, remember to switch the phone receiver from side to side. Better yet invest in a high quality speaker phone.
Breathe deeply while doing these stretches:

Press your forehead into your palms resisting forward motion with your hands. Hold for 15-30 seconds. Clasp your hands behind your head and press your head back. Resist any motion with your hands, holding for 20 seconds. Turn your head to one side, resisting any motion with your hand. Switch sides and hold for same amount of time on each side. Then, tilt head to one side, resisting any movement with your hand, again, holding the position for 20 seconds on each side.

Step away from your desk. Shrug your shoulders up to your ears, hold 5-7 seconds, then release. Repeat 3 times. Rotate each shoulder separately forward for 7 seconds and then backward for the same amount of time. Place your left arm (bent at elbow) up and over your head. Then grasp upper arm with right hand and pull it gently, slowly toward you, while leaning a little to the right. Feel the stretch all down your side and in your back. Repeat this with your right arm. For upper back tension relief, interlace fingers behind head and scrunch shoulderblades together and hold for 3-7 seconds, then release. Repeat a few times. Shake your hands at your sides, overhead, in the air and everywhere. Shake your whole body. This will boost sluggish circulation and help keep muscles loose.

For a pick-me-up, do this:
Beginning at your shoulder, gently "slap" your arm down to your wrist. Do the same thing to the other arm. Then, pat your chest - this stimulates the thymus, the heart of the immune system. Be sure to go to the middle of the breastbone. Then pat your stomach. Next pat your legs down to the tops of your feet. Complete by doing the same to your head, neck, back and buttocks. You'll feel tingly and energized by the end of this "exercise."

For the Neck and Shoulders

To loosen a stiff neck and sore shoulders, do these with a straight spine and BREATHE DEEPLY while sitting:

1. Slowly drop your head fully forward, then backward. Then tilt, then rotate to each side. Hold each position for
5 seconds or longer.

2. Turn your head slowly as far to the right as COMFORTABLE
Then, hold for 4 seconds. Repeat the above for the other side. Continue until you feel an easing of tension.

3. Grasp as much of the top of your left shoulder you can with your right hand, squeeze firmly for 5 seconds and let go quickly. Repeat on other shoulder. Do each shoulder 3 times.

4. Open and close your mouth widely, several times to relax the jaw which in turn, helps relax the neck.

To Calm and Energize

Anytime you want to feel calmer and more centered, close your eyes, inhale and exhale very slowly at least four times through your nostrils. Let your exhale be longer than your inhale. If you wish, with a relaxed attention, count to 4 on your in breath and 5 on your out breath. This exercise will increase your energy level.

If would like to increase work productivity, turn on an easy listening station. Their music is geared to the mood changes people typically go through in the course of a day. Lively and upbeat to get moving in the morning, stimulating tunes during the prelunch slump and relaxing music for day's end. Another way to increase work efficiency and effectiveness is to be physically fit and strong. This will give you more vitality which will in turn raise your productivity. For desk bound executives, this can be a challenge. NordicTrack has risen to meet that challenge. Their new product, The Executive Power Chair was designed with the corporate person in mind.

It doubles as a high-quality office chair and a strengthening device that allows '90s executives to build their upper body strength and muscle tone while taking care of business. You can use it while on conference calls or while reading. All of the major muscle groups can be effectively exercised in just 10 to 20 minutes. A basic 3 day a week workout on the Power Chair can build muscle and bone mass, tone flabby stomachs, increase energy level and relieve stress. It's a great way to get in shape while on the job! For more information contact NordicTrack.

For Home-Workers

If you spend long hours at your home computer working or playing, you may experience certain discomforts that can be avoided. If you have a cat, take the "Kitty Kat Kure." Lay back in your recliner or your favorite place to relax with your cat on your lap or chest. Researchers say that petting a pet relieves stress, lowers your blood pressure and heartrate. Do a jigsaw puzzle. This can slow you right down. Run around the block, take a short, brisk walk. Do some some of the exercises mentioned earlier in this section. Do yoga or improvised stretches. Remember to take "breathing breaks." Inhale to the count of four and exhale to the count of five. Be inventive, make up your own! Take a comedy break. Tape some comedy acts. Watch a clip or two when you really need a laugh. Find SOMETHING to laugh at - maybe even yourself! Laughter can save your life.

The following technique called "progressive relaxation" is best done while lying down:

Beginning with feet, say to yourself: " My feet are now beginning to relax. I am now relaxing my feet. My feet are TOTALLY relaxed." Then move up to your calves, get the picture, until you've covered every part of your body. When you get to your head say: "I am now relaxing my forehead, I am now relaxing my entire head." Now, I will relax my mind, etc. Repeat the phrase 2-4 times. Do this at least once a day. This one works well for getting to sleep quickly. It can be done in 2-3 minutes. However, it's most effective when you take 5-10 minutes. A simplified version is to close your eyes (if in a bank line or waiting room, leave eyes open - if more comfortable), take a deep in breath expanding the stomach while saying "I am." On the out breath, say "relaxed" or "peaceful" or whatever word or phrase works best for you.

Relax Your Eyes

Every hour or so, palm your eyes. This is done by getting into a reclining or lying down position, then rub your hands together until heat is generated, then place your palms over your eyes, your right hand slightly over your left. Leave them there while breathing naturally, deeply and fully for 3-5 minutes - less if time is limited. Relaxing the eyes calms your body and mind.

For the most part, what we have discussed in this section have been preventive techniques. Like anything else, relaxing is a skill that requires learning. It is a habit that you establish for yourself. It's one of the best insurances against injury. If you already have CTD symptoms, all the experts say to REST. This means, if possible, to take some time off. These injuries will respond to rest - BEST if attended to soon enough. The stretching and exercises offered here, focusing on flexibility and strength will help at any stage. However, rest is best. People have had excellent results using massage and other forms of physical therapy. If you must stay on the job, alternating applications of heat and ice have helped some. Braces or wrist splints can protect injured tendons and force larger muscles to carry more of the load. Remember if you are experiencing any numbness, pain or tingling, see your practitioner or physician immediately! You will gain by saving yourself from pain and some very costly surgery. It is always better to prevent than to recover.

Consider transferring to another department or reduce the workload, if possible. In fact, this may be the VERY opportunity you need to take a look at ALL aspects of your work situation. Is your workplace competitive or cooperative? An atmosphere of competition will create stress and tension. Whereas, an atmosphere of cooperation will create relaxation and harmony. Perhaps its time to contemplate a career change? Those of you who feel "stuck" in the 9-5 world - are you waking up dreading going somewhere you'd rather not be, doing something you'd rather not do? Without quitting your present job, you might consider network marketing as a viable way to start your own business. This business can be launched on a part-time basis right from where you area with a very small investment. For additional information, please see: "Attitude", "Relationships" and "Suggested Reading."

Are You Asleep Yet?

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