Safety Articles

Article # 10103


Eye and visual discomforts associated with video display terminal (VDTS) use is a common and growing health problem in the workplace. A study conducted by the American Optometric Association (AOA) found more than 10 million Americans experience visual discomfort and related symptoms due to operating VDTs. Computer glare was rated as the most frequent VDT ergonomic problem.

Causes and Symptoms of Eye Discomforts (associated with VDT use)

• Direct glare is commonly caused by natural light from windows, improperly positioned desk lamps, and fluorescent lighting fixtures.
• Indirect glare occurs when light from computer screens and glossy surfaces, such as desktops, inks, floors, etc. are reflected into the VDT users' eyes.

There are two forms of indirect glare; Specular or Diffuse
• Specular reflections are mirrored light images on the monitor screen that cause glare by bouncing into the eyes of the VDT user.
• Diffuse reflections, on the other hand, occur from light penetrating the glass and is reflected from within the computer screen.

Risk Factors
• Prolonged VDT use
• No interventions to reduce glare from all source
• Poorly designed or arranged workstations
• Accumulation of dust and other airborne particles that collect on a computer screen

• Eye strain
• Headaches
• Blurred vision
• Dry and irritated eyes
• Fatigue and decreased productivity
• Neck and backaches from straining to see

Proactive Approach
• Educate and train workers on proper eye positions when working at VDTs - center of the computer screen needs to be positioned seven to 10 inches below a users horizontal line of sight.
• Take short eye breaks and look away from the computer screen frequently.
• Provide an antiglare glass filter that can be placed directly over the computer screen.
• Provide adjustable workstations, tables and chairs. Make sure workers know how to reposition these items to properly fit them.