Poor lighting can result in eye strain, fatigue and aching which in turn is likely to lead to deterioration in performance, particularly if work relies on visual equipment such as computer-based job roles (Parsons 2000, Nave 2004).

As this type of work is now common place, the importance of lighting for visual health and performance at work is likely to become increasingly important.

Light is important to our well-being and performance. The quality of modern artificial light has improved, but the most comfortable and economical light still comes from the sun, although not sufficient and often combined with artificial light. As a result, not only the amount of light, but also the quality of light is important. Both need to be adapted to the working circumstances in a room.

The light reflecting capacity of a ceiling will not only contribute to a reduction in electricity bills but will also improve the quality of lighting conditions.

Next to sunlight and artificial light we can make a distinction between direct and indirect light. Direct light will light directly, whereas indirect light is the result of light reflection.

As the ceiling is the only surface in a room that is completely visible, the light reflection should be as high as possible to make effective use of the light.

Light reflection indicates the percentage of light which is reflected by the ceiling and is measured with a Y value. The Y value describes the percentage of light which is reflected by a surface. This value is relevant for lighting specialists when measuring lighting needs.

A ceiling with the right combination of high light reflection and a good spread of light (light diffusion) leads to a uniform and accurate spread of light in a room, leading to a smaller need for light fixtures. A higher light diffusion value leads to less dazzle and avoids mirror effects.