IES LM-80-21

This Approved Method describes the procedures by which solid-state light sources, such as LED packages, arrays and modules; or laser diode packages, arrays and modules may be tested for flux maintenance over time, including luminous flux, radiant flux, and photon flux maintenance. This document also provides methods for measurement of spectrum-dependent characteristic maintenance, including changes in chromaticity coordinates, peak wavelength, dominant
wavelength, centroid wavelength, and spectral power distribution over time, when carried out under controlled environmental and operational conditions. For the purposes of this document, solid-state light sources include ultraviolet, visible, and infrared sources emitting optical radiation in the range of 200 nm to 2,000 nm.

This Approved Method does not cover lamps, light engines, or luminaires and does not provide guidance regarding predictive estimations or extrapolation for the maintenance characteristics beyond the duration of the actual measurements.