Making the Door Zone Safe for Bikers

The door danger zone- where cars and cyclists intersect - is getting a revamp in San Francisco, highlighting how little room there is on the streets for all users.

1 minute read

September 2, 2011, 12:00 PM PDT

By Tim Halbur


The door zone in cities is a dangerous area for cyclists. It is the three feet of road closest to parked vehicles where doors open and close without much notice for cyclists.

Cyclist/door incidents are the second most common cause of injury while biking, according to The San Francisco Municipal Transportation Agency (SFMTA). To alleviate the problem SFMTA has painted new lines on the streets to identify the door zone area.

"On sections of Polk Street, the SFMTA has painted in a batch of T's in the bike lanes that are supposed to guide bicyclists away from the door zone. While the treatment seems to be an improvement over typical door zone lanes, it also highlights how little street width is available for cyclists to ride safely."

"Streetsblog San Francisco says studies performed by the SFMTA show the added lines have increased the average distance from the curb cyclists ride from 10.3 feet to 10.9 feet. While that may not seem like a lot, it was enough that the number of cyclists riding in the door zone on Howard Street, one of the trial streets, dropped from 24 percent to 10 percent. Riders on Polk Street moved from an average 10 feet to 10.4 feet from the curb, and door zone cyclists dropped from 41 percent to 30 percent."

Thanks to Cathie Pagano

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