An Enhanced Systemic Approach to Safety

To date, the dominant approach used by state agencies to allocate safety resources is the hotspot approach, which focuses on identifying and recommending improvements for high collision concentration locations. Another approach is the systemic approach that seeks blanket improvements that can be implemented at sites across the road network, based on specific roadway features that are associated with a particular crash type. While the hotspot approach is reactive in the sense that it focuses exclusively on sites that already had crashes, the systemic approach has both reactive and proactive components to it. The systemic approach is reactive since it uses historical crash data to identify the type of roadways that suffer from recurring safety concerns, and it is proactive in the sense that it provides a mechanism to make improvements at sites that share the same design and operational attributes - but have not had many (or any) crashes yet. The systemic approach is typically used in parallel to the hotspot approach and is considered a complement rather than an alternative. This study will develop a prototype tool for conducting a systemic safety analysis for a scalable area. At the core of the proposed approach is a transparent systemic crash matrix that shows what types of crashes occur on what types of facilities. The different rows in the systemic matrix represent different crash types, while the columns represent different facility types. The cells of the matrix are referred to as crash profiles and include the number of crashes that occurred for each crash profile. This method provides an agency with a simple to assemble, simple to interpret, snapshot of any systemic problems on their network, or study area. The anticipated outcomes of the study are: (i) a prototype tool for conducting a systemic safety analysis that can be conducted simultaneously for all modes of traffic, along with a set of possible engineering and non-engineering countermeasures; and (ii) a systemic tool that can provide agencies with the ability to make systemic data-driven blanket improvements across a desired area to support system-wide safety improvement.


  • English


  • Status: Active
  • Contract Numbers:


  • Sponsor Organizations:

    Office of the Assistant Secretary for Research and Technology

    University Transportation Centers Program
    Department of Transportation
    Washington, DC  United States  20590
  • Managing Organizations:

    Collaborative Sciences Center for Road Safety

    University of North Carolina, Chapel Hill
    Chapel Hill, NC  United States  27514
  • Project Managers:

    Sandt, Laura

  • Performing Organizations:

    University of California, Berkeley

    Berkeley, CA  United States  94720-1720
  • Principal Investigators:

    Grembek, Offer

  • Start Date: 20170301
  • Expected Completion Date: 20180228
  • Actual Completion Date: 20180228
  • USDOT Program: University Transportation Centers Program

Subject/Index Terms

Filing Info

  • Accession Number: 01627997
  • Record Type: Research project
  • Source Agency: Collaborative Sciences Center for Road Safety
  • Contract Numbers: 69A3551747113
  • Files: UTC, RiP
  • Created Date: Feb 24 2017 3:18PM