NEW YORK (CBSNewYork/AP) — New York City is launching a measure designed to keep pedestrians, bicyclists and motorcyclists from getting trapped under a truck in a collision.

Mayor Bill de Blasio said Monday that the city will start retrofitting more than 200 of its trucks with side guards this year.

“We are committed to using every tool in our box – enforcement, education, and engineering – to save lives and make our streets safer,” said de Blasio. “Installing side guards on our city trucks will help prevent fatal collisions.”

Side guards are rails between the front and rear wheels of a truck.

“All too often when a truck turns across the path of a walker or a bicyclist it’s all too easy for that person to get caught under those rear wheels so this is really a countermeasure that prevents cyclists or pedestrians from being caught under the rear wheels of a turning truck,” Paul Steely White of Transportation Alternatives told WCBS 880’s Rich Lamb.

Cyclists or pedestrians could be knocked down by a glancing blow from the side guards, which Steely White said “can still be serious, but not nearly as serious as getting caught under those big rear wheels.”

The mayor said the expansion to 240 vehicles will make New York City the largest municipal fleet in the nation to install truck side guards.

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