Hosting: Signal Timing Subcommittee

Hosting: Signal Timing Subcommittee

Welcome to the webpage for the Signal Timing Subcommittee within the TRB on Traffic Signal Systems Committee (AHB25).

Signal Timing Manual, First Edition

Subcommittee Chair: Jim Powell (

Secretary:  Nithin Agarwal, Ph.D. (

The Signal Timing Subcommittee promotes the research and understanding of concepts related to developing and maintaining traffic signal timing. A primary focus is the NCHRP/FHWA Signal Timing Manual (STM, see link below) based on the latest research and advancements in the field. The subcommittee highlights ongoing research related to the topic and best practices from various agencies across the country, and proposes updates to the STM. Part of the work is guiding systematic incorporation of research findings. The overall goal is to keep the STM current for practitioners to understand signal timing concepts, develop basic and advanced signal timing plans, and maintain traffic signal timing for their agencies.

2017 Agenda: [link]

Signal Timing Manual – First Edition – 2008

Signal Timing Manual – Second Edition – 2015 

Signal Timing Manual, Second Edition

The Subcommittee values comments and suggestions for the STM, as well as regarding the entire topic of signal timing. Please contact either Jim Powell or Nithin Agarwal by email with any input you would like to provide.

Return to Parent committee: AHB25: The Traffic Signal Systems Committee


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