The 85th Percentile Rule, Explained

A video explainer of the notorious traffic law that explains why some cities have to raise speed limits to enforce traffic safety.

1 minute read

October 8, 2020, 8:00 AM PDT

By James Brasuell @CasualBrasuell

To understand the scale of the challenge that must be overcome to achieve Vision Zero safety goals to eliminate traffic fatalities and to break the strangle hold cars have on U.S. cities, look no further than the 85th Percentile Rule, as neatly explained in the Grist video shown above.

For more background, see past Planetizen coverage of the 85th Percentile Rule.

FULL STORY: A 1930s city planning rule has drivers setting their own speed limits

Wednesday, October 7, 2020 in Grist

Transportation United States Traffic Safety speed limits 85th Percentile Traffic Laws Enforcement Car-Centric Planning View More

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