TRB's National Cooperative Highway Research Program (NCHRP) Web-Only Document 146: Replacement Processes for Light Emitting Diode (LED) Traffic Signals explores the photometric requirements, measurement, and maintenance of traffic signal modules using light emitting diodes (LEDs).

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NCHRP Web-Only Document 146 contains an incomplete Acknowledgments section. The complete Acknowledgments section is provided.

ACKNOWLEDGMENTS

The authors acknowledge sponsorship of this research from the National Cooperative Highway Research Program (NCHRP) of the Transportation Research Board. Helpful input was provided by members of the NCHRP Project 20-7/246 panel, by Guillermo Ramos, Abdus Salam, John Litteer, and Michael Naumiec of the New York State Department of Transportation, by Tony Blasczyk of the Wisconsin Department of Transportation, by Marty Vitale of the American Association of State Highway Transportation Officials (AASHTO) and by Mark S. Rea and Lei Han of the Lighting Research Center, Rensselaer Polytechnic Institute. The authors would also like to gratefully acknowledge the City of Los Angeles, the Nebraska Department of Roads, the New Jersey Department of Transportation, the New York State Department of Transportation, and the Wisconsin Department of Transportation for providing traffic signal modules to the project team for evaluation.