FEDS AND LEDS: ITE SPECIFICATION SHOULD GOVERN LED TRAFFIC SIGNAL PURCHASES

The US Federal Government has effectively adopted as a national standard the specification for light-emitting diode (LED) traffic signals, TCSH Part 2, published by the Institution of Traffic Engineers (ITE) in 1998. It is presented in the US Government Manual on Uniform Traffic Control Devices for Streets and Highways (MUTCD). Although it was published as an interim specification, VTCSH Part 2 can be expected to define both the ITE and international standards for LED traffic signals for the foreseeable future. As all major manufacturers of LED traffic signals have complying products, the standard's requirements are both reasonable and feasible. One of the critical factors addressed by the standard is the intensity of LED signals and its decrease as temperature rises; green LEDs are much less sensitive than yellow and red LEDs to temperature. In addition to temporary decrease of light intensity at higher temperatures, LEDs are subject to long-term, permanent degradation of light output as their hours of operation increase. To compensate for these effects, drive current and the total number of LEDs in the signal must both be increased. Although there are not yet any standards in place for LED-based traffic arrows and signals at pedestrian crossings, the ITE is now developing them.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/32663949
• Corporate Authors:

  Cap Gemini

  ,    

  PB Farradyne

  444 South Flower Street, Suite 3700
  Los Angeles, CA  United States  90071

  iMPath Networks

  ,    

  Georgia Department of Transportation

  One Georgia Center
  600 West Peachtree Street, NW
  Atlanta, GA  United States  30308

  Pantech

  ,    

  System Innovations, Incorporated

  1551 Forbes Street
  Fredericksburg, VA  United States  22405
• Authors:
  • ADINOLFI, J
• Publication Date: 1999

Language

• English

Media Info

• Features: References;
• Pagination: p. 22-3,25-6
• Serial:
  • Traffic Technology International
  • Publisher: AutoIntermediates Limited
  • ISSN: 1356-9252
  • Serial URL: http://www.ukipme.com/mag_traffic.htm

Subject/Index Terms

• TRT Terms: Color; Crosswalks; Federal government; Information management; Information, data, and knowledge; International; Luminous intensity; Sensitivity; Standards; Temperature; Traffic signals
• Geographic Terms: United States
• ITRD Terms: 6784: Colour; 183: Government (national); 8555: Information documentation; 9034: International; 505: Light intensity; 1659: Pedestrian crossing; 5928: Sensitivity; 187: Specification (standard); 6722: Temperature; 565: Traffic signal; 8122: USA
• Subject Areas: Data and Information Technology; Highways;

Filing Info

• Accession Number: 00782745
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Files: ITRD, STATEDOT
• Created Date: Feb 7 2000 12:00AM