LED TRAFFIC SIGNAL INDICATIONS: SAFETY IMPLICATIONS

Over the past several years, cities from Philadelphia, Pennsylvania, to Anaheim, California, have initiated programs to replace incandescent lamps with light-emitting-diode (LED) technology. While the movement toward the use of LEDs has occurred nationwide, the major concentration of replacement programs has been in California. The most common motivation of the agencies that undertook conversion programs was energy reduction and, indirectly, monetary savings. However, few, if any, of the early installing agencies made a specific quantitative determination that the LED devices were as good as or better than incandescent lamps in communicating with drivers. It is now recognized that the design and operating characteristics of LED traffic signal modules can affect the safety of both the motoring public and the personnel who maintain the system. Some of the safety benefits are immediately available, while others will only be realized over a longer period. LED modules meeting the requirements of the Institute of Traffic Engineers (ITE) Interim Specification maintain the required intensity over the warrantied life of the module over a wide range of operating conditions including temperature and line voltage. Unlike incandescent lamps, LED modules are current dependent and will not dim during brownout conditions. Another safety benefit is the longer life of the LED modules, which reduces the number of maintenance calls to an intersection. This means a reduction in the probability that an incident will occur involving maintenance crews.

• Supplemental Notes:
  • Full conference proceedings available only on CD.
• Corporate Authors:

  Institute of Transportation Engineers (ITE)

  Washington, DC  United States 
• Authors:
  • Sullivan, T D
• Conference:
  • Enhancing Transportation Safety in the 21st Century ITE International Conference
  • Location: Kissimmee, Florida
  • Date: 1999-3-28 to 1999-3-31
• Publication Date: 1999

Language

• English

Media Info

• Pagination: 4p

Subject/Index Terms

• TRT Terms: Cost effectiveness; Crash rates; Electric current; Energy conservation; Incandescent lamps; Light emitting diodes; Luminous intensity; Maintenance; Modernization; Safety; Savings; Service life; Traffic safety; Traffic signals
• Subject Areas: Design; Energy; Environment; Highways; Maintenance and Preservation; Operations and Traffic Management; Safety and Human Factors; I73: Traffic Control; I85: Safety Devices used in Transport Infrastructure;

Filing Info

• Accession Number: 00768848
• Record Type: Publication
• Files: TRIS
• Created Date: Sep 14 1999 12:00AM