Synthesis of Safety for Traffic Operations - Transports Canada

Synthesis of Safety for Traffic Operations March 2003
where:
N = Number of crashes per year
ADT m = Average two-way major road traffic per day
ADT s = Average two-way side street traffic per day
PL s = Proportion of peak hour traffic approaching on the side street that is turning left (%)
T = Proportion of peak hour traffic approaching the intersection that consists of trucks (%)
L T = 0 if the major road does not have a protected left turn; 1 if the major road has at least one protected turn
phase
V = 0.5 * (V m + V s )
V m = the sum of the absolute percent grade change per 100 feet for each vertical curve along the major road, any
portion of which is within 800 feet of the intersection centre, divided by the number of such curves
V s = the sum of the absolute percent grade change per 100 feet for each vertical curve along the side street, any
portion of which is within 800 feet of the intersection centre, divided by the number of such curves
Bauer and Harwood (2000)
California
Urban, four-leg intersections
Stop-controlled:
where:
N = 0.009429 ADT main 0.620 ADT side 0.281 e -0.941X1 e -0.097X2 e 0.401X3 e 0.120X4 e -0.437X5 e -0.384X6 e -0.160X7 e -0.153X8 e -0.229X9
X1 = 0 if main road left-turns are permitted; 1 otherwise
X2 = Average lane width on main road (metres)
X3 = 1 if the number of lanes on main road is 3 or less; 0 otherwise
X4 = 1 if the number of lanes on main road is 4 or 5; 0 otherwise
X5 = 1 if no access control on main road; 0 otherwise
X6 = 1 if right-turn is NOT free flow from main road; 0 otherwise
X7 = 1 if no illumination; 0 otherwise
X8 = 1 if the main road is a minor arterial; 0 otherwise
X9 = 1 if the main road is a major collector; 0 otherwise
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