Most experts agree that viewing video display terminals (VDTs) is not harmful to the eyes. However, extended periods of close work may cause eye strain. The effects of eye strain include blurred vision, headaches, tearing, and difficulty focusing. It's wise for computer users to take the following steps to prevent eyestrain:

• Use good workspace ergonomics. Position yourself between 20 and 30 inches from the VDT screen, with your eyes high enough that you're looking down on it. Also, be sure your VDT is free from dust.
• Avoid glare. Use drapes and blinds to control sunlight, and keep the glare of interior lights to a minimum. Keep bright flourescent lights and desk lamps out of your field of vision. Use VDT filter screens or a VDT hood to reduce glare. Special eyeglasses and tints are available that maximize your eyes' ability to focus on the VDT's soft images.
• Take short, frequent breaks. Take a break every 15 minutes and be sure to blink your eyes often and focus on both near and distant objects. Try to organize your work so you don't have to use a VDT for long stretches.
• Keep your lens prescription up-to-date. If you are beginning a job requiring much VDT work, have an eye exam before you start, and have frequent exams afterward.