IES TM-15-20

A careful selection of lighting equipment is critical to ensure that the positive aspects of outdoor lighting do not simultaneously create a nuisance for local residents. The issues of light pollution, glare, natural habitat, and the nighttime environment are best addressed when meaningful data regarding luminaire optics can be considered as the lighting application is designed. This document defines a luminaire classification system (LCS) for outdoor luminaires that provides information to lighting professionals regarding the lumen distribution within solid angles of specific interest. This system overcomes the many shortcomings of the old “cutoff” system and is intended to replace that now deprecated system. The LCS also includes Back Light, Uplight, and Glare (BUG) ratings.