Evaluation is performed using a standard lighting and viewing area by rating the appearance of specimens in comparison with appropriate reference standards. Lighting and evaluation should be carried out in a darkened room, using the equipment light source only. Any ambient light reflected could interfere with the rating results.

Viewing board incorporates either 2400 mm (8 ft) or 1200 (4 ft) Cool White lamps. The unit is switched and incorporates high frequency electronic control gear and can be either wall or mobile trolley mounted.

May be built to customer specifications.