Wearing a cycle helmet causes drivers to pass more closely

A psychologist and Avid cyclist in bath conducted an experiment to see if wearing a helmet whilst cycling affected the behaviour of drivers passing him. He used ultrasound sensors to measure the distance between passing cars and his bicycle.

His findings, published in the March 2007 issue of Accident Analysis & Prevention, state that when Walker wore a helmet drivers typically drove an average of 3.35 inches closer to his bike than when his noggin wasn't covered. But, if he wore a wig of long, brown locks—appearing to be a woman from behind—he was granted 2.2 inches more room to ride.

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