This paper describes comparisons of traffic safety during the morning and afternoon peak hours in extended stretches of eight High Occupancy Vehicle (HOV) lanes with two different types of access – four corridors with continuous access and the others with limited access. Traffic collision patterns in two different types of HOV lanes were investigated by evaluating 1) the differences in collision distribution, severity, types of collisions and per lane traffic utilization, 2) spatial distribution of collision concentrations by using Continuous Risk Profile (CRP) approach, and 3) collision rates in the vicinity of access points in HOV lanes with limited access. In the paper, the authors conducted detailed analysis on collision data occurred during peak hours in relation to geometry and traffic features. Based on the findings from the assessment on eight routes, the limited access HOV lanes appear to offer no safety advantages over the continuous access HOV lanes. Such difference is due to more frequent and sporadic distribution of collision concentration in limited access HOV lanes.
April 1, 2008