Human Factors Guidelines for Road Systems, Proposed 4th Edition

The Human Factors Guidelines for Road Systems (HFG), published as NCHRP Report 600 is a tool for considering road user characteristics into roadway design and operational decisions. The HFG provides guidelines for individual intersection, roadway segment, and other element types and is currently being revised to update existing information and to address additional elements, including bicycle facilities, pedestrian facilities, and roundabouts. Additional critical gaps in guidance on considering human factors were identified during the early stages of planning for the first HFG materials, and users have indicated that development of these materials would be beneficial to their efforts to reduce fatalities and serious injuries. At inception, it was envisioned that the HFG would be a living document where new guidelines would be developed as new human factors needs are identified for enhancing road users’ safety and as new research studies and data become available to serve as the source of guideline materials. It was recognized that some topics could not be developed in the initial HFG publications and future editions would be driven by practitioner needs. The 3rd Edition will add new chapters on bicycles, pedestrians, and roundabouts after responding to a survey of desired HFG changes to increase modal understanding and newer intersections concerns. Similarly, after receiving user input the 4th Edition is proposed to have new chapters on transit, older road users, road diet, and complete street topics. The HFG end users also indicated a need for support with application of the HFG in countermeasure selection, road safety audits, roadway signage reviews, determination of crash contributing factors, root cause analysis, human factors training and teaching. Further, the research also intends to include updates to existing chapters that could not be updated in the 3rd Edition as other human factors and safety research has continued to evolve rapidly in recent years. The 4th Edition would include new practice-ready content—guidelines, tutorials, tools, etc. that support and illustrate how data-driven safety analysis tools (such as the AASHTO Highway Safety Manual, (HSM)) and performance–based-decisions reflecting road user needs, capabilities, and limitations will enhance highway safety. The objective of this project is to review existing published highway–related human factor road-users research literature; update as needed existing guidelines in HFG, Edition 3, and develop new technical chapters with guidelines for inclusion in HFG, Edition 4. All new guidelines will use the format as published in the Edition 3 of the “Human Factors Guidelines for Road Systems,” NCHRP 600. The research also intends that the HFG be a supplement and coordinated document with the AASHTO HSM and other safety tools and processes such as road safety audits, operational reviews, performance planning, data driven design and operations of the road system.


  • English


  • Status: Proposed
  • Funding: $550000
  • Contract Numbers:

    Project 22-46

  • Sponsor Organizations:

    National Cooperative Highway Research Program

    Transportation Research Board
    500 Fifth Street, NW
    Washington, DC  United States  20001

    American Association of State Highway and Transportation Officials (AASHTO)

    444 North Capitol Street, NW
    Washington, DC  United States  20001

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Project Managers:

    Jared, David

  • Start Date: 20200914
  • Expected Completion Date: 0
  • Actual Completion Date: 0

Subject/Index Terms

Filing Info

  • Accession Number: 01707551
  • Record Type: Research project
  • Source Agency: Transportation Research Board
  • Contract Numbers: Project 22-46
  • Files: TRB, RiP
  • Created Date: Jun 3 2019 3:17PM