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What is Lamp Life?

  Lamp life is a measurement of a luminaire’s lifespan. This number is calculated based on median hours of burning time under ANSI test conditions.  

How is Lamp Life Tested in LED Lamps?

  LED lamp life is gauged by the depreciation in lumen output. Many manufacturers express lamp life in terms of “L70”—the number of hours a lamp burns before depreciating to 70% of its original output.    But again, that’s most manufacturers. There is no universal protocol for measuring lamp life in LED luminaires. Different manufacturers use different reference points and different testing conditions. While LEDs offer a longer lifespan than HID bulbs in general, it’s always a good idea to get full testing information from your manufacturer. A quality LED manufacturer will always be prepared to clarify how they calculated their advertised lamp life.