Evaluating the Safety Impacts of Flashing Yellow Permissive Left-Turn Indications in Massachusetts: Approach Level Analysis - Phase II

Identifying the safety contributions of the Flashing Yellow Arrow (FYA) permissive indication through an approach-level crash analysis. Understanding the benefits of infrastructure & opertational elements will likely improve performance at intersections with FYAs. Given the novelty of the Flashing Yellow Arrow (FYA) in Massachusetts, this research study will provide MassDOT with a greater understanding of their impacts from an approach-level perspective. More so, this study will provide the agency with a holistic overview of infrastructure and operational impacts at each of these intersections, ultimately leading to an improved understanding of future design characteristics. Approach level analysis is the most appropriate method to assess the true impact of the permissive indication as well as infrastructure (e.g. turn lane length, LT lane offset, etc.) and operational (e.g. clearance intervals, phase sequence, etc.) elements. Thus, this study will aim at evaluating the before/after crashes of these FYA intersections from the approach-level to better understand the safety impacts of the LT permissive FYA signal. The advancement of these crash data analytics, methodologies, and applications will continue to remain important in years to come, and will increase safety by providing an increased understanding of conflict risk at signalized intersections involving FYAs.


  • English


  • Status: Active
  • Funding: $115,000
  • Contract Numbers:


  • Sponsor Organizations:

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Managing Organizations:

    Massachusetts Department of Transportation

    10 Park Plaza
    Boston, MA  United States  02116
  • Performing Organizations:

    University of Massachusetts, Amherst

    Department of Civil and Environmental Engineering
    130 Natural Resources Road
    Amherst, MA  United States  01003
  • Principal Investigators:

    Tainter, Francis

    Fitzpatrick, Cole

  • Start Date: 20211101
  • Expected Completion Date: 20220930
  • Actual Completion Date: 0

Subject/Index Terms

Filing Info

  • Accession Number: 01857543
  • Record Type: Research project
  • Source Agency: Massachusetts Department of Transportation
  • Contract Numbers: 109600
  • Files: RIP, STATEDOT
  • Created Date: Sep 13 2022 5:14PM