Bicycle Crash Typing
The development of effective roadway design and operation, education, and enforcement measures to accommodate bicyclists and prevent crashes is hindered by insufficient detail in computerized state and local crash files. Analysis of these databases can provide information on where bicycle crashes occur (city, street, intersection, two-lane road, etc.), when they occur (time of day, day of week, etc.), and characteristics of the victims involved (age, gender, injury severity, etc.). Current crash files cannot provide a sufficient level of detail regarding the sequence of events leading to the crash.
In the 1970s, methods for typing pedestrian and bicycle crashes with motor vehicles were developed by the National Highway Traffic Safety Administration (NHTSA) to better define the sequence of events and precipitating actions leading to pedestrian- and bicycle-motor vehicle crashes.6,7,8 These methodologies were applied by Hunter et al. in a 1996 study to more than 8,000 pedestrian and bicycle crashes from six states.9 The results provided a representative summary of the distribution of crash types experienced by pedestrians and bicyclists. Some of the most frequently occurring bicycle crash types include:
- A motorist failing to yield (21.7 percent of crashes)
- A bicyclist failing to yield at an intersection (16.8 percent of crashes)
- A motorist turning or merging into the path of the bicyclist (12.1 percent of crashes)
- A bicyclist failing to yield at a midblock location (11.7 percent of crashes)
- A motorist overtaking a bicyclist (8.6 percent of crashes)
- A bicyclist turning or merging into the path of the motorist (7.3 percent of crashes)
The crash-typing methodology described above has evolved over time and has been refined as part of a software package known as the Pedestrian and Bicycle Crash Analysis Tool (PBCAT).10 The development of PBCAT was sponsored by FHWA and NHTSA. Those interested may register for the PBCAT software and user’s manual from the Pedestrian and Bicycle Information Center Web site at http://www.bicyclinginfo.org/bc/pbcat.htm. An update of this software will soon be available on the Web site.
PBCAT is a software product intended to assist state and local pedestrian and bicycle coordinators, planners, and engineers with the problem of lack of data regarding the sequence of events leading to a crash. PBCAT accomplishes this goal through the development and analysis of a database containing details associated with crashes between motor vehicles and pedestrians or bicyclists. One of these details is the crash type, which describes the pre-crash actions of the parties involved. The more than 70 specific bicyclist crash types used in PBCAT may be collapsed into 20 crash-typing groups. Several of these groups (including rarer or unusual crash types) have been further combined into 14 BIKESAFE groups for purposes of selecting treatments. A few PBCAT types that include rarer or difficult to remedy crashes that cannot be very specifically defined are not treated in the Crash Matrix. Some of these types of crashes are discussed in group 14 in the Definitions of Bicycle Crash Types page. Examining the closely-related crash groups for countermeasures could be helpful, as well as using the Performance Objectives Matrix to identify appropriate countermeasures.