Bicycle Railing Height Report - AASHTO - Subcommittee on Design

DETERMINATION OF APPROPRIATE RAILING HEIGHTS FOR BICYCLISTS
NCHRP 20-7 (168)
many states require that serious bicyclist crashes not involving a motor vehicle be
reported, research indicates that these types of crashes are underreported. 5
<strong>Report</strong>ing systems do allow retrieval of crash data involving road features, such as guide
rails or bridges; however, it is difficult to retrieve specific information involving a
bicyclist crash with a railing. Additionally, motor vehicle crash surveillance systems
generally provide only information for crashes between vehicles and bicyclists that
involve a serious injury. Overall, these systems are not reliable sources of information
for bicycle/railing crashes not involving motor vehicles. Data retrieval from the systems
for crashes involving railings is difficult, and would require review of the actual crash
reports to determine if the crash involved a railing.
Crashes <strong>Report</strong>ed Through the Survey and Outreach Process
The state and advocacy surveys solicited information regarding specific bicycle crashes.
If a respondent indicated that he/she possessed knowledge regarding a crash, an
additional survey form would appear at the end of the standard survey. This additional
survey form solicited basic information about the crash, and requested permission for a
follow-up phone call.
The survey reported a total of six bicycle crashes involving a railing. Three crashes
occurred in the United States, two occurred in England, and one occurred in Canada.
Overall, statistical analysis of six crashes would not be reliable. However, information
from these crashes provided characteristics of bicycle railing crashes, and offered useful
information related to the design of bicycle railings. Follow-up phone calls were made to
acquire specific information about the details of the crash.
Additional crash information related to railings was acquired through the outreach
process. During one crash, a bicyclist lost control on a shared-use path on a bridge after
colliding with a pedestrian. With no railing separating the path from traffic lanes, the
bicyclist fell into the path of motor vehicle traffic. During another crash, two bicyclists
collided with a motor vehicle on a bridge. The bicyclists were thrown over the bridge’s
railing. The type and size of the railing were not reported. Finally, another bicyclist
collided with an object in the road and fell over a vehicular railing.
The bicycle crashes are summarized in Table 2 below. Of the nine crashes, five occurred
on roadway bridges, two occurred on a shared use path and two occurred on a shared use
path on a bridge. In four of the five roadway bridge crashes, the railing consisted of a
vehicular railing less than 1.1 meters (42 inches) high (the height of the railing in the fifth
crash is unknown). Two of the six crashes involved a motor vehicle (bicyclists were hit
by an overtaking motor vehicle).
Two of the crashes involved a 1.4-meter (54-inch) high railing. During both of these
crashes, the bicyclists were traveling at excessive speeds. One of the bicyclists lost
5 R. Brustman, “An Analysis of Available <strong>Bicycle</strong> and Pedestrian Accident Data,” New York Bicycling
Coalition, 1999, p.4.
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