NACTO Recommends Default Safety Setting for Speed Limits

A step toward an overhaul of the way speed is managed on city streets around the country.

1 minute read

August 2, 2020, 7:00 AM PDT

By James Brasuell @CasualBrasuell


Parking and Driving

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"The National Association of City Transportation Officials (NACTO) [in July] released a guide urging local leaders to rethink how they set speed limits on city streets in a bid to prevent pedestrian deaths," reports Chris Teale.

The "City Limits" guide recommends that cities "[set] default speed limits on many streets at once, designate slow zones in what they deem "sensitive areas" and set speed limits on major corridors by using studies that take into account density and activity level."

NACTO describes this guidance as furthering goals set forth by the National Transportation Safety Board (NTSB) in 2017 to completely overhaul how speed is managed on U.S. streets, including the way that speed limits are set. 

Teale cites NACTO Program Manager Jenny O'Connell in stating that NACTO's new guidance would recommend the demise of the 85th percentile rule, "which involves measuring 100 drivers traveling without traffic and setting the speed limit based on the 15th-fastest driver." The 85th percentile rule has been used by some jurisdictions to justify higher speed limits for the sake of enforcement.

Monday, July 27, 2020 in Smart Cities Dive

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