Synthesis of Safety for Traffic Operations - Transports Canada

Synthesis of Safety for Traffic Operations March 2003
CHAPTER 7: BICYCLE SAFETY
Wheeler (1992)
Wheeler (1992) examined the effectiveness of advanced stop lines for cyclists at three
signalized intersections in the United Kingdom. An advance stop line provides cyclists
with a four to five metre storage area downstream of the stop line for vehicles, thereby
permitting cyclists to advance through the intersection before motor vehicles, reducing
the risk of conflict. The layout of a typical advance stop line is shown in Figure 7.1.
Ped. Crosswalk
Bicycle Lane
Motor Vehicle Lane
4m - 5m
FIGURE 7.1: Typical Layout of an Advance Stop Line for Cyclists
The pavement markings, as shown in Figure A, were supplemented with advance
warning signs, and an auxiliary traffic signal head placed at the “setback” stop line for
motor vehicle traffic. The auxiliary signal head was comprised of a typical three-section
signal head supplemented with a fourth section that displayed a green bicycle symbol
while the approach rested in “red”. The idea was to indicate to cyclists that they may
proceed to the downstream stop line (where the primary and secondary heads were
visible and displaying a red indication). Site selection was not based on an unusually
high incidence of cyclist crashes.
A naïve before-after analysis of crash frequency was employed to assess the safety
impacts of the advance stop lines. The results are shown in Table 7.1.
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