Current international knowledge on the safety of the different types of at-grade intersections and of the principal intersection design elements is reviewed and summarized. There appears to be substantial agreement between the results of accident studies carried out in different countries. Roundabouts appear to have considerable safety advantages over other types of at-grade intersection and are now being widely used in many countries. Little quantitative information is available on the relationships between a number of intersection parameters and safety. An international comparison of at-grade intersection design practices, including the principal elements of simple major minor intersections, speed-change lanes and roundabouts, is made. There are considerable differences in design practices due to differences in the design assumptions.
Abstract