What good is LM-80 testing?
LM-80 testing and TM-21 extrapolations are intended to ensure that lumen
maintenance meets expectations for LED lighting. LM-80 ensures consistent
testing protocols for all LED manufacturers. TM-21 ensures consistent lumen
maintenance extrapolation methods for all LED manufacturers.
TM-21 6x rule is intended to limit length of lumen maintenance predictions. Note
that 6,000 hours of testing, allows lumen maintenance claims up to 36,000 hours.
TM-21 Lp extrapolations are ‘best-case’ system lifetime estimates, and assume
that no other failure mechanisms influence the life of the LED luminaire.
‘Real-world’ system lifetime predictions also need to consider other types of
possible failures, such as drivers, electrical interconnections, and random wearout
failures.