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Good Computer Ergonomics Can Eliminate Computer Related Aches and Pains
The American Optometric Association (AOA) recommends good computer ergonomics to help reduce the symptoms of computer vision syndrome (CVS). As high tech as the term computer ergonomics sounds, it really amounts to a few simple adjustments and arrangements for your computer workstation. CVS symptoms affect both vision and body structures. Vision Symptoms and Computer Ergonomics
Accommodation, the ability to focus quickly between objects at different distances, can be affected by long periods of computer work. Your range of vision on the screen and your reference papers is limited to the intermediate visual zone. It is smaller than the range of vision for general work, which requires that your eyes adjust quickly between near, intermediate and far distances. Over time your range of vision may be narrowed unless you take breaks and look away from the screen frequently. Children's eyes are not fully developed. Studies of children using computers show a trend toward nearsightedness as they spend more and more time in front of a computer. Adults’ vision can become blurry unless precautions are taken. Other vision symptoms include dry eyes from reduce blinking frequency and eyestrain. Eyestrain includes irritation, itching, pain from straining against glare and focusing on the lighted screen. Physical Symptoms and Computer Ergonomics
Vision symptoms aren’t the only problems associated with CVS. Physical symptoms like headaches, and pains in the neck, shoulders and back are common, too. Workstation Setup and Computer Ergonomics
Screen Settings: Take advantage of the screen’s brightness and contrast settings to find the most comfortable combination for your eyes. Screen refresh rate should be set at the highest rate possible, and no less than 75 Hz. Resolution should be the highest your monitor can provide. Anti glare screens are better than glossy ones as there is less glare. If you have a glossy screen, consider attaching an anti-glare screen. Also, keep the monitor directly in front of you. Looking at a monitor placed off to the side can cause neck and shoulder pain. Keep your screen clean, too. Most computers and many software programs have features that let you increase your font size, or zoom to a larger view. With today’s larger screens this is a reasonable option as you can still enlarge the text and have it all visible without side-to-side scrolling. Room Lighting: Consider turning down the room lights so that the room and monitor are about the same light intensity. This will ease the strain on your eyes. Cover windows so that they don’t cast reflections on your screen, or even off of your glasses. Position your screen with windows and lamps to the side of it to reduce glare. Workstation Positions: Your screen should be between 18-28 inches from your eyes. Some recommendations narrow that to a range of 20-26 inches. Your chair should be at a height that allows you to sit straight with your feet flat on the floor, eyes at a level near the top of the screen so that you gaze downward about 10° to 20°. The downward gaze helps keep moisture from evaporating from your eyes. Your elbows should bend at 90° to reach the keyboard. This means the keyboard should be positioned about 26 inches from the floor. This is several inches below desktop level.
Computer Glasses: Computer glasses are designed to maximize the intermediate zone and can be made to precise prescription strength. Even small errors in prescription strength can strain your eyes. You can add anti-glare coatings to computer glasses and tints to help offset the straining effects of fluorescent lighting. Breaks: Take frequent breaks. Look away from the screen for several seconds, or even minutes every 20 minutes or so. Take a 10-minute break from looking at the screen every couple hours. Look around the room, get up and walk around. Just use your eyes at different distances and in different lighting. Blink often. Computer work encourages dry eyes. Blinking keeps them moist. Repetitive Tasks: Breaks give us a chance to use our hands, fingers, arms and body in other ways. Repetitive hand movements cause carpal tunnel. We need to stretch and walk, exercise our muscles and circulation. When possible break your computer work into smaller sessions throughout the day. Computer Ergonomics follow-up
People are not all the same size, and children are far smaller, yet. The above are basic guidelines. While the screen distance won’t change much when adjusted for children, obviously the height of everything will. If your child’s feet don’t set flat on the floor, make sure there is a footstool, crate, box or other flat surface for his feet. His hips and knees should bend at 90° just as an adult’s should. The screen should be set for his height so that he looks down at the same angle as an adult would. Just as you would modify your workstation for a child, set it up so that adults of different heights can also adapt the setup for their comfort. Don’t confuse standard eyeglasses with computer glasses. The intermediate zone in progressive lenses is much narrower in standard glasses. This would force the user to tilt his head to position them where he can see clearly. Bifocals have no intermediate zone and single prescription lenses would likely be for reading or distance vision. |