This Technical Note examines the light output (over time) of an LED light source, also known as LED lumen depreciation or lumen maintenance. Suggestions are made on ways to avoid rapid LED degradation, and the importance of good design is emphasized.

This document was produced by Lighting Global Quality Assurance. In February 2020, Lighting Global Quality Assurance evolved to become VeraSol, an independent program offering quality assurance services for solar energy kits and off-grid appliances.