Recommended lighting levels, expressed in foot candles, for 57 specific tasks and for general construction plants and underground work areas, with illustrations of lighting patterns and a general guide for recommended lighting levels. If a plant is more than 20 years old, the lighting system is almost certain to be outmoded. Consequences can be poor housekeeping, low morale, an abnormally high percentage of rejected parts or products, and a higher accident rate. Both quality of lighting (pertaining to brightness, glare, color, diffusion, direction, and uniformity) and quantity of illumination may be evaluated according to tasks. Brightness of a room should be relatively uniform. Reflected glare is frequently more annoying than direct glare. Color can improve visual comfort by lowering brightness contrasts and may be used to stimulate or soothe. Fluorescent lamps tend to minimize shadows. Lighting fixtures may include direct, semidirect, and indirect light sources according to visual perception needs. Maintenance includes cleaning and regular checks with a light meter of lighting efficiency. The foot candle is the unit used to compare lighting levels with standards; in comparing brightness ratios, the reflected light is usually measured in terms of the foot lambert. When conducting a lighting survey, both average illumination and localized lighting should be measured. Spot illumination should be metered from the position of the task.