Engineering Speed Management Countermeasures: A Desktop Reference of Potential Effectiveness in Reducing Speed
July 2014
This chart summarizes studies about engineering countermeasures used to manage speeds. Studies where an increase in speed were reported are also shown since this information is also relevant in selection of countermeasures.
Speed Volume (vpd) Mean Speed (mph) 85th %tile Spee 1 (mph) Countermeasure Safety Area Reference Limit Period Location Focus Roadway Sites Notes
(mph) Before After Before After Change Before After Change Vertical Deflections Within the Roadway
pedestrian urban 1 (1999) 178 46 to various
11544 110443
400 to 401 to
pedestrian urban local 2 (2005) 3384 26 VA
4362
Speed Hump-rounded, pedestrian urban local 3 (2000) 475 to 433 to 36 31 raised area placed across 1506
the roadway, typically 12 to pedestrian urban local 4(2005) 1300 29 1-mon 14 feet long 218 to
pedestrian rural/urban local 5(2002) 28 22 1-mon
pedestrian urban 1 (1999) 36 29 with speed table
pedestrian urban 1(1999) 2456 to 2593 to 38 25 -13 with choker 3685 2931
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