Quality and Longevity Standards in LED Lighting
LM-80 and TM-21 standards are critical metrics that determine LED quality and lifespan. Learn why these standards matter for your lighting investment.
What is LM-80?
"IES LM-80" is a laboratory test standard applied by LED manufacturers to test the luminous flux (lumen) and color change performance of LED components (especially LED chips) over time.
Tests are typically conducted for 6,000, 10,000, or 12,000 hours at specific temperatures (e.g., 55°C, 85°C, 105°C).
This test observes how much light loss (lumen depreciation) the LED chip experiences over time.
LM-80 tests are done only for the LED itself, not directly for LED modules or fixtures.
In other words, it provides a scientific answer to the question "How does this LED chip age over time, how much light does it lose?"
What is TM-21?
"IES TM-21" is a calculation method used to estimate the expected lifespan of an LED using data obtained from LM-80 tests.
Based on LM-80 test data, results like "This LED can maintain 90% light efficiency at the end of 50,000 hours" are derived.
The result is usually expressed as follows:
L80 @ 50,000 hours = LED maintains 80% luminous flux after running 50,000 hours.
Expressed with statements like L90 @ 60,000 hours.
It answers the question "We have LM-80 data, what will this LED look like after 50,000 hours based on this?"
Why is it Important?
"The LED chips used in our products have been tested according to LM-80 standards and show L80 performance over 60,000 hours according to TM-21 calculations. This means safe and stable light quality for years."
