What Is the Utilization Factor in Lighting

The term utilization factor in lighting refers to what percentage of the actual light physically reaches the surface of the room. The utilization factor of a room can be affected and changed by several different components of the room.

How do you calculate utilization factor in lighting?

Utilization Factor is Proportion of light reaching working plane to the light output of lamps. UF = Lumens received on Working Plan / Lumens output of luminaires. The lighting manufacturers’ catalogues give Utilization Factors for standard conditions. The UF is expressed as a number which is always <1.

What is utilization factor and depreciation factor in illumination?

Depreciation factor = 1 / maintenance factor. Its value is always more than 1. Coefficient of utilization or utilization factor: It is defined as the ratio of total number of lumens reaching the working plane to the total number of lumens emitting from source.