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SECTION III--TYPE OF PROBLEM BEING ADDRESSED (Hunter et al. 1996). Both bicyclist and motorist are identified as contributing to the crash in 5 to 20 percent of crashes over various bicyclist ages. Motorists were deemed to be solely at fault in from 5 percent of crashes with the youngest aged cyclists to about 36 percent of crashes involving adults ages 50 to 59. Precipitating Events Crashes involving bicycles and motor vehicles are complex phenomena, and classifying the different events into mutually exclusive categories is a formidable task. Cross and Fisher (1977) were the first researchers to develop and apply crash `typology' for bicycle crashes as part of a NHTSA response to the 1,003 bicyclist fatalities in 1975. NHTSA also developed a coder's handbook for typing bicyclist crashes to address this issue (NHTSA, n.d.). Similar typology was used in the FHWA study by Hunter et al. (1996). In a six-state study of 3,000 bicycle crashes taken from hard copy police reports, the most frequent bicycle/motor vehicle crash types were as follows: Crossing Path Crashes % of All Crashes Motorist failed to yield to bicyclist (includes drive out/through 21.7 at intersections and midblock/driveway locations) Bicyclist failed to yield to motorist at an intersection 16.8 Bicyclist failed to yield to motorist, midblock 11.8 Other crossing path crashes 7.2 57.5 Parallel Path Crashes Motorist turned or merged into bicyclist's path 12.2 Motorist overtaking bicyclist 8.6 Bicyclist turned or merged into motorist's path 7.3 Other parallel path crashes 7.4 35.5 Specific Circumstances Crashes 7.0 (such as off-roadway, backing vehicle, intentional, and other unusual crash types). Crash type proportions varied by state, however, likely reflecting differences in urbanization and other characteristics. The most severe crashes, as measured by the percentage of involved bicyclists seriously injured or killed, were as follows: Crossing paths Bicyclist turning error (23.8 percent) Bicyclist failed to yield, midblock (22.1 percent) Bicyclist failed to yield, intersection (20.1 percent) Parallel paths Operator loss of control (34.6 percent) Wrong-way operator (most often the bicyclist) (32.1 percent) III-10

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SECTION III--TYPE OF PROBLEM BEING ADDRESSED Motorist overtaking (29.4 percent) Bicyclist turn/merge into the path of a motorist (25.2 percent) The high proportions of severe crashes, therefore, were all parallel path crashes. Crossing path crashes occur at junctions (intersections or driveways) and more often in urbanized areas where speeds are often slower. Children tend to be over-represented more often in crossing path crashes including ride outs at non-intersection locations (such as driveways) and at intersections, failing to clear an intersection, and turning errors, and in turn/merge maneuvers in front of motorists traveling on parallel paths. Adults tend to be over-represented in parallel path crashes (which tend to be more severe) including motorist overtaking crashes, motorist turn/merge in front of bicyclist on a parallel path, as well as in bicyclist overtaking motorist crashes. The crash typologies developed by Cross and Fisher, by NHTSA, and in the FHWA study evolved into the development of an automated crash typing software, the Pedestrian and Bicycle Crash Analysis Tool (PBCAT) (Harkey et al., 1999), which is currently being further refined for version 2. These and other studies have resulted in the identification of a number of specific crash types that have been classed into thirteen groups (plus an additional miscellaneous group comprising non-roadway, and some rarer and unusual crash types) for the purposes of identifying appropriate countermeasures. The definitions of these crash groups are shown in Exhibit III-6. EXHIBIT III-6 Example Bicycle/Motor Vehicle Crash Types and Descriptions Crash Group Example Image 1. Motorist failed to yield-- signalized intersection Description--The motorist drove into the crosswalk area or intersection and collided with the bicyclist. The motorist either violated the signal or did not properly yield right-of-way to the bicyclist. 2. Motorist failed to yield--non- signalized intersection Description--The motorist drove into the crosswalk area or intersection and collided with the bicyclist. The motorist either violated the sign (stop, yield, flashing signal) or did not properly yield right-of-way to the bicyclist. III-11

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SECTION III--TYPE OF PROBLEM BEING ADDRESSED EXHIBIT III-6 (Continued) Example Bicycle/Motor Vehicle Crash Types and Descriptions Crash Group Example Image 3. Bicyclist failed to yield-- signalized intersection Description--The bicyclist rode into the intersection and collided with the motorist. The bicyclist either violated the signal or did not properly yield right-of-way to the motorist. 4. Bicyclist failed to yield--non-signalized intersection Description--The bicyclist rode into the intersection and collided with the motorist. The bicyclist either violated the sign (stop, yield, flashing signal) or did not properly yield right-of-way to the motorist. 5. Motorist drove out--midblock. Description--The motorist drove across the sidewalk or into the street from a non- intersection location (including residential or commercial driveway or other midblock location) without yielding to the bicyclist. 6. Bicyclist rode out--midblock. Description--The bicyclist rode into the street from a non-intersection location (including residential or commercial driveway or other midblock location) without yielding to the motorist. III-12

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SECTION III--TYPE OF PROBLEM BEING ADDRESSED EXHIBIT III-6 (Continued) Example Bicycle/Motor Vehicle Crash Types and Descriptions Crash Group Example Image 7. Motorist turned or merged left into path of bicyclist. Description--The motorist made a left turn or merge into the path of a bicyclist traveling in the same or opposite direction. 8. Motorist turned or merged right into path of bicyclist. Description--The motorist made a right turn or merge into the path of a bicyclist traveling in the same or opposite direction. 9. Bicyclist turned or merged left into path of motorist. Description--The bicyclist made a left turn or merge into the path of a motor vehicle traveling in the same or opposite direction. 10. Bicyclist turned or merged right into path of motorist. Description--The bicyclist made a right turn or merge into the path of a motor vehicle traveling in the same or opposite direction. III-13

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SECTION III--TYPE OF PROBLEM BEING ADDRESSED EXHIBIT III-6 (Continued) Example Bicycle/Motor Vehicle Crash Types and Descriptions Crash Group Example Image 11. Motorist overtaking bicyclist Description--The motorist was overtaking the bicyclist at the time of the crash. 12. Bicyclist overtaking motorist Description--The bicyclist was overtaking the motorist (passing on the right or the left) at the time of the crash. (Includes crashes involving bicyclists striking parked cars or extended doors.) 13. Non-motor vehicle crashes. Description--These crashes do not involve a motor vehicle and may occur in a variety of ways including bike only falls, bike-bike, bike-pedestrian, and bike into object crashes. III-14

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SECTION III--TYPE OF PROBLEM BEING ADDRESSED EXHIBIT III-6 (Continued) Example Bicycle/Motor Vehicle Crash Types and Descriptions Crash Group Example Image 14. Other and non-roadway crashes Description--Includes a variety of specific crash types such as turning errors by the bicyclist or motorist, head-on crashes resulting from the bicyclist or the motorist traveling in the wrong lane, intentional crashes, other unusual crashes, and crashes occurring in parking lots, driveways, and other off-roadway areas. III-15