There is no convincing scientific evidence that VDTs are hazardous to the eyes. However, since complaints of eye discomfort and fatigue are becoming more common as VDT use increases, safety concerns have naturally arisen.

Extensive testing in government laboratories has established that VDTs emit little or no harmful ionizing radiation (such as X-ray) or non-ionizing radiation (such as ultraviolet) under normal operating conditions. In fact, the amount of ultraviolet radiation produced by VDTs is a small fraction of that produced by fluorescent lighting. The levels of radiation from VDTs are well below those required to produce cataracts or other eye damage even after a lifetime of exposure.

Can VDTs Be Associated With Eyestrain?

Yes. A variety of symptoms including eye irritation (red, watery or dry eyes), fatigue (tired, aching heaviness of the eyelids or forehead), and difficulty focusing may be noticed. Headaches, backaches, or muscle spasms may also occur. Fortunately, these complaints often result from conditions that can be remedied by either changing elements in the workstation design or providing proper glasses for the user.

Though eyestrain is an annoying symptom, it is not an indication that use of the eyes must be discontinued to avoid permanent damage. Instead, a systematic search for the cause should be made. Your ophthalmologist can examine you to rule out eye disease and provide proper glasses, if you need them. The distributor of the VDT equipment may also give helpful suggestions regarding workstation modifications.

How Can Eyestrain Be Prevented?

At the workstation, most VDT users prefer a viewing distance a little farther away than they normally read. The top of the VDT screen is most comfortably placed at or slightly below eye level. The reference material should be as close to the screen as practical to minimize large head and eye movements and focusing changes.

Lighting should be arranged so reflections and glare are minimized. Sometimes standard office lighting is too bright for comfortable VDT use. If modification of the office lighting is not practical, hoods and neutral density or micromesh filters for the VDT may help.

The VDT screen is a good dust collector and should be wiped often with an antistatic cloth to improve visibility.

Periodic rest breaks are important. Use of a VDT requires a fairly unchanging body, head, and eye position that can be fatiguing. Frequent blinking will lubricate the eyes and prevent them from drying out.

What Are The Special Needs Of VDT Users?

The VDT screen must be kept in proper focus. Since the screen is usually placed farther away and higher than the usual reading distance, different glasses may be necessary. This is especially true for individuals who wear bifocals, trifocals or reading glasses. A bifocal height may need to be raised to compensate for the higher positioning of the VDT. The additional visual demands of VDT use may mean that some individuals who normally do not need glasses should have corrective lenses for this activity.
Your ophthalmologist can prescribe the correct glasses for you. You will need to describe the layout and dimensions of your workstation for the ophthalmologist to calculate the lens power that will work best for you.

In addition, the comprehensive medical eye examination you receive from your ophthalmologist or optometrist will help diagnose whether the discomfort you experience with VDT use is due to simple eyestrain or whether unsuspected disease is present.

Reference: American Academy of Ophthalmology