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  • Door Zone

sharrow-bikelane.jpg

The Door Zone is the four to five feet next to a parking lane where car doors swing open. This is a particular problem for bicycle riders when bicycle lanes are placed next to a lane of cars parked parallel to the curb, or where no bicycle lane exists.   Door zone crashes can result in serious injury or death, as chronicled by a bike activist, in Ann Arbor, Michigan [1].  In most the fatal cases noted, the bicyclist was thrown into the path of a passing vehicle after striking the car door.  Door zone crashes have been found to represent 5% of crashes in Boston, Massachusetts, and 16% in Santa Barbara, California.[2]


Bicycle Lanes

The initial study on bicycle lane widths was done on curb-side bicycle lanes (reference link needed). Some bicycling advocates recommend that bicycle lanes placed next to parking lanes should be 3 feet wider and/or with a painted indicator that bicycles shouldn't travel in the door zone.

Sharrows

Where streets are not wide enough to accomodate bicycle lanes, bicyclists may dangerously ride close to parked cars, ride on the wrong side of the street, or ride on the sidewalk, all of which are dangerous.  Riders who ride a safe distance from the door zone are often subject to harrassment and sometimes unsafe and threatening maneuvers from vehicle drivers.  To combat this problem, a number of U.S. cities, including San Francisco, California, Seattle, Washington, Denver, Colorado, Gainesville, Florida, and Cambridge, Massachusets, have installed a painted legend known as a Sharrow (share + arrow). The centerline of the sharrow is placed 11 feet from the curb (about 4 feet from parked vehicles). The Sharrow reminds both car drivers and bicyclists that bicycles are welcome, despite the absence of a bike lane, and that bikes should ride outside of the door zone. A study in Gainesville showed that bicyclists rode a few inches further away from parked cars following the installation of sharrows, indicating they have a positive impact. [1]


ALSO ON THE LIVABLE STREETS NETWORK



REFERENCES

Each source is referred to by the same number every time it is cited. Please keep citation style consistent.

[1] Riin's Rants, The Door Zone Project.

[2] Pein, W. Bicycling and On-Street Parallel Parking. Online publication. 2003.

[3] Alta Planning and Design, for San Francisco Department of Traffic and Parking. San Francisco's shared lane pavement markings: improving bicycle safety. 2004.

[4]

PICTURE REFERENCES

Pictures are cited in the order they appear above. Please keep citation style consistent.

[1] New York sharrow marking.  Photo by Aaron Naparstek, via Streetsblog

[2]

FURTHER READING


KEYWORD

Sharrow, bicycle crash, bike lane, parked car, parallel parking

About this article:

Door Zone

Created July 14, 2008 by Michael Snyder
Edited September 1, 2009 by Andy Hamilton (view changes)

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