LM80 is third party testing to report lumen maintenance.
LM80 specifies testing up to 60,000 hours. TM21 recommends a method for projecting the results of the LM80 tests beyond 60,000 hours to arrive at a reasonable estimate of LED “life.”
What is Lumen Maintenance?
- LED emitters typically do not burn out or “die” in the practical life of any LED product; they fade in intensity. So the concept of “lamp life” has been replaced by the concept of “lumen maintenance.”
- Lumen maintenance is generally a prediction of the number of hours an emitter will operate before it fades below a usable level of intensity. Currently, most lumen maintenance reporting assumes that dropping below 70% intensity is the end of life for an LED emitter.
- LED lumen maintenance is typically reported as a total number of hours with a “B” number and an “L” number. ETC rates it’s LED fixtures with a lumen maintenance value of 50,000 hours (B50, L70). This is a very common rating in the LED fixture industry. This indicates that after 50,000 hours of use, 50% of the LEDs tested (B50) will fall below 70% of their initial lumen output (L70).
- These metrics indicate the probability that a single LED will fail lumen maintenance under precise test conditions, not necessarily a system of LEDs, or the drivers and power supplies used in a luminaire.