Explain the Traffic Safety - Transportation

Crash rates are normally considered better indicators of risk than crash frequencies.

 a. Crash rates for intersections are normally expressed in terms of crashes per million entering vehicles (MEV), using the following equation:

R_int = A * 10⁶ / (365*T*V)

b. Crash rates for roadway segments are normally expressed in terms of crashes per 100 million vehicle-miles (100 MVM), using the following equation:

R_sec = A*10⁸ / 365 * T * V * L

Where:  R_int = crash rate for the intersection 

R_sec = crash rate for the roadway section

    A    = number of reported crashes

    T    = time period of the analysis (years)

    V   = annual average daily traffic volumes (veh/day)

    L   = length of the segment (miles)