How far is far enough?
by Preston Tyree, Director of Education - League of American Bicyclists
Door zone crashes may be responsible for 7 percent of the crashes that cyclists encounter. But they are responsible for a larger percentage in urban traffic, as much as 17 percent of the fatal crashes, as reported in one New York City report.
Cyclists who consistently ride in the "door zone" (that space that is next to a parked car that can be obstructed by an opening door) are setting themselves up for a case of road rash at best and possibly a serious injury or death. So, how far away from a parked car is far enough?
I'm not going to give you an exact number but some guidelines to help you decide for yourself. However, here is an example of another cyclist finding a safe place to ride: (sorry, the youtube video is no longer available)
First, many people and writings suggest that three feet away from the cars is safe. That is too close, particularly if "three feet" translates in your mind to be about an arm's length away. If you can touch the mirror, you are too close.
Park your car along a curb. Make sure you are the legal distance from the curb, usually 12 to 18 inches. Then open the door and line up your bicycle so your handlebar is about six inches away from the farthest point on the door. That might seem good enough, but it probably isn't. If you are riding there and that door came flying open, you would probably shy to the left - into the middle of the travel lane.
How far from an open car door do you feel comfortable riding? Leaving your car door, take your bike down the road and take a few trial runs past the car. Figure out where you are comfortable riding past that open door. Remember to take into account that two-door models and larger cars have a much wider door zone than a smaller or four door vehicle.
I read that a 1977 Ford Torino two-door had a door that measured 12.5 feet (from the curb) when fully open.
I suspect that you will find yourself riding about where you would be if you had a "door zone dummy" riding on your right side. At least that is the way I visualize it.
To be really safe around a complex grouping of cars and trucks, you may have to ride as much as 13 feet from the curb. That means that on most streets in Austin, you would be controlling the lane, as you don't want cars passing you without leaving three feet of clearance. That means that the 13 feet, plus the width of your handlebars and the three-foot clearance puts the nearest a car could safely pass at about 17 feet (from the curb).
Article originally published in Southwest Cycling News, Volume XIX, No. 9, October 2009, front page. Photos courtesy of Preston Tyree and Fred Meredith.