NCHRP 17-76 “Guidance for the Setting of Speed Limits” was published on 3/31/20. It may just be one of the most influential research efforts related to speed limits. The objective of the research was 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. Learn from the principal investigator on the project that looked for ways 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.
Host: Ryan Zellers, Department Manager – Traffic Engineering, Michael Baker International, Western District Advertising Manager
Randy McCourt, ITE International Past President (moderator)
Kay Fitzpatrick, Senior Research Engineer at Texas Transportation Institute