National Traffic Speeds Survey I: 2007

A field survey was conducted during spring and summer 2007 to measure travel speeds and prepare nationally representative speed estimates for all types of motor vehicles on freeways, arterial highways, and collector roads across the United States. Over 10 million vehicle speeds were measured at more than 700 sites included in the geographic cluster sample of 20 primary sampling units (PSUs). Each PSU was a city, county, or group of two or three counties representing combinations of regions of the United States, level of urbanization, and type of topography (flat, hilly, mountainous). Speeds were acquired on randomly drawn road segments on limited access highways, major and minor arterial roads, and collector roads. Speed measurement sites were selected in road segments with low, medium or high degrees of horizontal and vertical curvature or gradient. Overall, speeds of free-flow traffic on freeways averaged 64.7 mph and were approximately 11 mph higher than on major arterials, which at 53.6 mph were in turn about 7 mph higher than the mean speed of 46.9 mph on minor arterials and collector roads. Most traffic exceeded the speed limits. Nearly half of traffic on limited access roads and about 60% of traffic on arterials and collectors exceeded the speed limit. About 15% of traffic exceeded the speed limit by 10 mph or more on freeways, arterials and collector roads. Speeds of passenger vehicle size classes were generally higher than for medium trucks. Often, speeds of large trucks were higher than medium trucks, and in some circumstances, large truck speeds were higher than passenger vehicles.

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• Record URL:
  https://rosap.ntl.bts.gov/view/dot/1941
• Corporate Authors:

  Westat

  1650 Research Boulevard
  Rockville, MD  United States  20850

  National Highway Traffic Safety Administration

  Office of Behavioral Safety Research, 1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Huey, R
  • De Leonardis, D
  • Shapiro, G
  • Freedman, M
• Publication Date: 2012-8

Language

• English

Media Info

• Media Type: Digital/other
• Edition: Final Report
• Features: Appendices; Figures; References; Tables;
• Pagination: 98p

Subject/Index Terms

• TRT Terms: Arterial highways; Average travel speed; Field studies; Freeways; Speeding; Traffic speed
• Uncontrolled Terms: Collector roads; Speed estimates
• Geographic Terms: United States
• Subject Areas: Data and Information Technology; Highways; Safety and Human Factors; I73: Traffic Control;

Filing Info

• Accession Number: 01449580
• Record Type: Publication
• Report/Paper Numbers: DOT HS 811 663
• Contract Numbers: DTNH22-02-D-65121; TASK ORDER 6
• Files: HSL, NTL, TRIS, ATRI, USDOT
• Created Date: Oct 19 2012 3:52PM