Improving and Communicating Speed Management Practices

Speed limits are among the most visible and routinely enforced traffic control devices motorists encounter in their everyday driving. They are also associated with safety in a broad range of forums, from neighborhood residents concerned with their children's safety to national safety agencies calling into question the rationale for speed limit setting procedures used by the vast majority of engineering practitioners. Given this high degree of exposure and scrutiny, speed limits – and the practices and procedures used to develop them, inform drivers, and help enforcement of them – must be appropriate for their environment, defensible from an engineering and legal perspective, and comprehensible to the full range of mobility and safety stakeholders. In short, speed limits are a highly complex engineering, human factors, and political issue belied by the simplicity of a black-on-white, two-digit regulatory sign. This research work plan is designed to increase the profession’s understanding of the fundamental relationships between posted and operating speed, develop consistent procedures for the establishment of posted speed limits and the use of technologies to increase driver awareness and comprehension, and provide content to support external and internal TxDOT dialog about speed limits and their development for all roadway environments. Historical procedures for posted speed limit setting based on 85th percentile speed will be leveraged for their utility, where appropriate, but revised to current practice based on sensitivity to roadway characteristics and driving environment context.


  • English


  • Status: Completed
  • Funding: $501,006
  • Contract Numbers:


  • Sponsor Organizations:

    Texas Department of Transportation

    125 E. 11th Street
    Austin, TX  United States  78701-2483

    Federal Highway Administration

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

    Texas Department of Transportation

    125 E. 11th Street
    Austin, TX  United States  78701-2483
  • Project Managers:

    Pridgen, Shelley

  • Performing Organizations:

    Texas A&M Transportation Institute, College Station

    Texas A&M University System
    3135 TAMU
    College Station, TX  United States  77843-3135
  • Principal Investigators:

    Fitzpatrick, Kay

  • Start Date: 20191220
  • Expected Completion Date: 20220831
  • Actual Completion Date: 20220831
  • Source Data: TxDOT Research Library

Subject/Index Terms

Filing Info

  • Accession Number: 01743949
  • Record Type: Research project
  • Source Agency: Texas Department of Transportation
  • Contract Numbers: 0-7049
  • Files: RIP, STATEDOT
  • Created Date: Jun 24 2020 7:16PM