Significant numbers of bicycle commuters, once limited to cities such as Portland, Oregon, have become an increasingly familiar sight across the United States. In a survey by the American League of Bicycles, other top cities include Minneapolis, Seattle, San Francisco, New Orleans and Honolulu. This trend has been encouraged by new bike-sharing systems, bicycle-specific infrastructure and “complete streets” initiatives.

Despite such gains, bicycle commuting isn’t without risk, particularly when cyclists must share streets designed to maximize automotive speed and traffic volume. A 2010 study by Monash University, Australia, “Identifying Risk Factors for On-road Commuter Cyclists,” sought to better understand risk factors by equipping cyclists with helmet-mounted cameras over a four-week period.

More than 127 hours of data were gathered and the behavior of cyclists and drivers analyzed. Fifty-four car-cyclist interactions were recorded and classified by severity. Two were collisions, 6 near-collisions and 46 were incidents. The results include:

• Prior to events, 88.9% of cyclists traveled in a safe and legal manner
• Vehicle drivers were at fault in 87% of the events, with more than 83% of drivers showing no post-event reaction
• The most frequent event was caused by drivers suddenly changing lanes, 40.7%
• 70.3% of events occurred at an intersection or intersection-related locations
• Cyclists who frequently looked over their shoulders had the highest situational awareness and the greatest ability to avoid collisions or near-collisions with cars

The authors suggest that strategies be implemented to increase drivers’ awareness of cyclists, particularly when turning or changing lanes.

Tags: bicycling, bicycle, bikes, cars, safety

By Leighton W. Klein | December 1, 2010