What is Lumen Depreciation?
Lumen depreciation refers to the gradual loss of a lamp’s original light output. The reverse term is “lamp maintenance,” defined as the light output remaining over time.
Using Lumen Depreciation to Define LED Lamp Life
When you see the rated life of an LED light, you may see the code “L70.” This means that the lamp’s rated life is a reflection of how many hours of operation you can expect before the light output has reduced to 70% of its original output. In other words, LED lamp life does not tell you when the light burns out completely. Rather, it’s a reflection of the rate of lumen depreciation.