Traffic Safety Requires a 'Psychological Speed Limit'

New York Governor Andrew M. Cuomo signed a bill this month reducing the speed limit in New York City. But what will it take to get people to actually slow down, especially when speeding is an acceptable social norm?

1 minute read

August 18, 2014, 5:00 AM PDT

By James Brasuell @CasualBrasuell


Tom Vanderbilt follows on New York State's adoption of a bill that lowers the default speed limit in New York City to 25 miles per hour by asking a question that gets at "a sterner challenge to the new limit." That is, how will the city convince drivers to obey the new speed limit? "What, after all, is so dangerous about driving 5 or 10 m.p.h. above the new speed, a difference the driver may hardly register?"

After stating that there are only two ways to lower the speeds of drivers (speed bumps and speed cameras), Vanderbilt makes an argument that a far more powerful force must be addressed before speeds will stop killing people: social norms. Stated simply, "New York City needs to look like a city where driving above 25 m.p.h. seems not simply dangerous, but inappropriate." 

Thursday, August 14, 2014 in New York Times

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I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

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