North Carolina Department of Transportation
Research & Innovation Summit – 2021

LED Traffic Signal Lifespan and Replacement Assessment

Authors: Morgan Westbrook, William Rasdorf, Fred Kish
NC State University
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  • LED Traffic Signal Modules in North Carolina: 28,000
  • Currently no national guideline for LED Replacement
  • Warranty of 5 years (prior to 2021)
  • Warranty of 15 years (since 2021)
  • Failure Mode: Illuminance Degradation
  • Estimated life expectancy: exceeds warranty period
  • Illuminance Standards: minimums set by ITE