Guidance for the Setting of Speed Limits

The objectives of this research were to (1) identify and describe factors that influence operating speed and (2) provide guidelines to make informed decisions related to establishing speed limits on roadways. The guidelines are to address the following: (a) an approach for determining the relationship between operating, design, posted and statutory speeds and how the differences among them impact safety performance; (b) identification and classification of nationwide data including, but not limited to, geometric design, access density, signal density, traffic volume characteristics, and enforcement practices that may impact operating speed; (c) an analysis of the 85th percentile speed and other statistical measures and factors as appropriate methods for setting speed limits; (d) implications of setting a speed limit lower than those recommended using the factors identified above. The focus of the research was on roadway functional classifications of minor arterials and higher as defined by AASHTO.


  • English


  • Status: Completed
  • Funding: $500000
  • Contract Numbers:

    Project 17-76

  • Sponsor Organizations:

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590

    American Association of State Highway & Transportation Officials (AASHTO)

    444 North Capitol Street, NW, Suite 225
    Washington, DC  United States  20001

    National Cooperative Highway Research Program

    Transportation Research Board
    500 Fifth Street, NW
    Washington, DC  United States  20001
  • Project Managers:

    Jared, David

  • 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: 20161007
  • Expected Completion Date: 20200331
  • Actual Completion Date: 20200331
  • Source Data: RiP Project 40216

Subject/Index Terms

Filing Info

  • Accession Number: 01572384
  • Record Type: Research project
  • Source Agency: Transportation Research Board
  • Contract Numbers: Project 17-76
  • Files: TRB, RIP
  • Created Date: Aug 7 2015 1:01AM