Lighting

In an office environment, it is important to consider both the overall lighting level and the position of lights and windows. For computer work, excessively bright lighting can cause visual discomfort, especially when it creates glare on the computer monitor. Inadequate lighting can also result in eye strain particularly when working with paper documents. Compared to computer work, paper-based work often requires a higher lighting level, such that additional task lighting may be necessary. Older workers may need a higher lighting level to compensate for visual limitations due to age.

Glare

Glare occurs when there is a large difference in light levels within the visual field. Glare can lead to visual fatigue and discomfort as the eyes try to adapt to the differences in light levels. You may also adopt an awkward body position in order to avoid either direct or indirect glare.

Direct glare occurs when a source of bright light, such as a task light or an unshaded window, is directly in your field of view. Indirect/reflected glare occurs when light bounces off nearby surfaces into your field of view. Both types of glare can be distracting and impair your ability to view the computer monitor.

To optimize the office environment with respect to lighting, the following should be considered:

  • Lighting levels should be adequate for the type of tasks performed at the workstation.
  • The monitor should be free from glare or reflections from other light sources such as windows and overhead lighting.
  • If task lighting is used, it should be positioned so that it does not shine directly in your eyes and does not cause shadow or glare on the computer monitor or source documents.
  • Your line of sight should be parallel to the plane of the window; curtains and blinds can also be used to control light from windows.
  • Walls, floors, and work surfaces should have low reflectance (matte finish) to reduce reflections.