Coefficient of utilization

Also found in: Wikipedia.

Coefficient of utilization

A measure of the efficiency of a light fixture: the ratio of the luminous flux reaching a surface to the total lumen output of the fixture. This is found in the photometric test report as the percentage of total lamp lumens generated within the fixture that actually reach the work plane. It is based on the efficiency of the fixture.

coefficient of utilization, Brit.

utilization factor. The ratio of luminous flux received on the work plane to the total luminous flux emitted by the source.
References in periodicals archive ?
Lumen output, luminaire coefficient of utilization, room sizes and their reflectance, and lamp and luminaire depreciation all have tolerances associated with them.
We need to appreciate lumens, luminance and coefficient of utilization, for example, just to read a cutsheet.
In every coefficient of utilization (CU) table, the first column of figures, for rooms with the highest reflection factors (RFs), have much higher values than the CUs in the last column for the darkest rooms.

Full browser ?