Computer Display Hazards

Are VDTs Harmful to your eyes?

Since they were first introduced nearly 30 years ago, computers-or video display terminals (VDTs)- have become a routine part of many jobs. Millions of people at work, school and home spend hours each day working at a computer. To get the most benefit from that time spent at a computer, its important that you make your workstation comfortable, and use equipment that adds to your productivity. Due to the dramatic increase in computer use-not only in the workplace but also in the home-complaints of eye fatigue and discomfort are common. Many people assume increased computer use is the source of these complaints. But extensive testing in government and private research laboratories has not produced scientific evidence that VDTs will harm your eyes. Research has established that VDTs emit little or no harmful radiation, such as x-ray, or non ionizing radiation such as ultraviolet rays. You might also be familiar with electromagnetic fields, which arise from such sources as power lines, electrical appliances and VDTs. Measurements of electromagnetic emissions from VDTs have shown these emissions are well below the levels of concern and that they pose no health risks.

Can VDT use cause eyestrain?

Although people who use VDTs on a regular basis often complain of eye irritation, fatigue and difficulty focusing, most of these symptoms are from other conditions surrounding the computer screen, such as poor lighting or improper placement of equipment and supplies. In some instances, a prior eye problem may be the cause. An examination by an eye doctor can determine whether you have an eye disease or you just need glasses to correct the problem. Undiagnosed eye problems may aggravate the risk of eyestrain during long periods of computer use.

How can changes in the workplace reduce eye discomfort?

Even the most well-planned office layouts can pose circumstances that are not ideal for VDT use. The lighting may be too bright or the workstations may be poorly arranged. Most users prefer a viewing distance a little farther away than for reading printed text. Keep the following checklist in mind when evaluating your workstation:

  • The computer screen should be placed slightly below eye level.
  • Reference material should be placed on a document holder and moved close enough to the screen so that you don’t have to swing your head back and forth from the material on the screen. If that happens your muscles may become stiff and sore, and your eyes have to constantly change focus, which can cause eye strain and headaches.
  • The lighting should be modified to eliminate glare and harsh reflections. If the office lighting or window shades cannot be adjusted, hoods or micro-mesh filters for the VDT may correct the problem.
  • Frequent breaks to stretch, stand up and rest your eyes are important. Since constant computer use requires you to sit in the same position with little exercise, changing tasks to take a break from the computer will help reduce eye fatigue.
  • To keep your eyes from drying out and feeling itchy, try blinking rapidly every once and a while. Use an artificial tears solution if you have been diagnosed as having dry eyes.

What else can make working at a computer more comfortable?

Here are some other tips that you should consider if your work requires a lot of time at the computer:

  • Get an adjustable chair; this allows you to position yourself at a proper angle and distance from your screen.
  • The screen itself should be 20 to 26 inches from your eyes, and slightly below eye level.
  • When selecting VDT equipment, choose a screen that swivels and tilts and has both brightness and contrast controls. A detachable keyboard is also a plus.
  • Using an adjustable copyholder that is placed close to the screen and at the same level will reduce eye and head movements that can cause fatigue.


Everyone should have periodic dilated eye examinations, especially those who are over 40. For people who use VDTs on a daily basis, periodic eye examinations by an eye doctor are doubly important. To receive the correct lens power, you should describe the layout and dimensions of your work station to your eye doctor, so that your doctor can calculate the prescription best suited for you