How long is life span of LED? Can it really reach 50000 hours?

When we talking about lifespan of LED, it refers to L70 which is when the lumen maintenance is 70% of the original level. Generally it is not convenient to test a LED lamp continuously for 50000 hours. So generally the lab will using accelerated aging test method to get the lumen depreciation situation after 6000 hours or 10000 hours , together with Decay curve fitting, to evaluate lifespan of LED. Currently there are two main standards of testing lumens depreciation, they are LM79 and TM-21. When the test reports meet standards of 50000 hours requirement, we can state the life span of the LED lamp reach 50000 hours.