LED Traffic Signal Repair and Replacement Practices

Abstract

Upgrading traffic signal systems from incandescent bulbs to LED modules over the last two decades has vastly improved the sustainability of this ubiquitous transportation asset. Recent technological upgrades have extended the warrantied life of these assets from 5 years to 15 years. With these advancements, it is vital that prioritization be given to sustainable operations and maintenance strategies which take advantage of the extended lifespan and continued reduction in energy consumption of LED modules. One major limiting factor in determining these strategies is that the service life of new 15-year-warrantied LED modules is currently unknown. Through available literature, this paper identifies the expected service life of 5-year-warrantied LED modules, commonly used from the early 2000s to 2022, as a baseline for comparison. Literature also provides insight into current Inspection, Repair, and Replacement practices. Interviews with manufacturers provide insight into current and future lifespan expectations. Finally, feedback from active transportation agencies provides examples of current practices in the absence of official national guidance, of which there is little. Understanding the current state of practice and expectations for the future will allow for the development of a repair and replacement guideline, ultimately taking maximum advantage of these advancements in sustainable technology.