It's Time To Reconsider How Speed Limits Are Set

Speed limits are currently determined by a calculation that considers only the status quo of vehicular velocity. Standard practices for speed limit setting and legislators should prioritize the safety of community members, according to this article.

2 minute read

August 9, 2020, 11:00 AM PDT

By Lee Flannery @leecflannery


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Tiffany Chu, founder of transportation company Remix, asserts that American we need to rethink the way we set speed limits in the United States. While transportation laymen may hope that speed limits are set by a calculation determining the safest rules for traveling by car in a given space, the reality it that safety considerations are simply not a part of the calculation. Instead, says Chu, speed limits are set "by the speed at or below which 85 percent of the motorists drive on a given road, an outdated guideline promoted by the Federal Highway Administration (FHWA)."

Chu reminds that speeding has played a part in about a third of traffic collision fatalities in the United States over the past two decades and that, given these statistics, government agencies need to revise the methods for setting speed limits and introduce speed-reducing street design mechanisms on busy roadways.

For Chu, design is at the center of the solution, pointing to a July report released by the National Association of City Transportation Officials (NACTO), which advocates for speed limits set by criteria like density and activity level in addition to designing slow zones. "We cannot usher in a multimodal future without lowering speeds and making streets safe for all users. We must support the work of those undoing harmful legacy methods, and encourage the adoption of policies that embrace and emphasize design," advises Chu.

Thursday, August 6, 2020 in Forbes

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