Synthesis of Safety For Traffic Operations

Safety is one of the most important and complex aspects of transportation engineering. It takes a traffic professional considerable time and effort to keep abreast of research in the field of safety as it relates to traffic engineering improvements. Reading through research reports and summarizing the results is an overwhelming task; especially when having to identify the constraints of each study and relate them to the situation under evaluation. The only accepted Canadian reference document related to traffic operations and engineering is the Manual of Uniform Traffic Control Devices for Canada (MUTCD). The MUTCD is basically, a collection of traffic control device standards with limited information on their safety benefits or how they should be used to improve safety. New studies and research findings are continuously presented and documented but not easily accessible by all transportation practitioners. Therefore, Transport Canada identified a need for a document that synthesized the safety impacts of various traffic operations and control strategies. The objective of this project was to assemble state of the art information from approximately the last ten years of research on the safety benefits of traffic engineering improvements. The final product would be a reference document providing, as much as possible, Canadian research information on the safety impacts of traffic control and operations that are most useful to transportation practitioners and other transportation professionals. As traffic operations and engineering is a vast topic, a Technical Advisory Team of provincial and municipal transportation engineering professionals from across Canada assisted in developing a list of relevant topics for inclusion in the Synthesis. The topics selected were: intersection control, traffic signs, pavement markings, pedestrian safety, bicycle safety, legislation and enforcement, turn lanes, and traffic calming. The information contained in the document was found from conventional literature searches of known databases, Internet searches using appropriate key words, and personal contact with Canadian academic and road safety practitioners. Only studies that reported on crash occurrence, crash severity, or crash surrogates with a proven correlation to crashes were taken into consideration. The research studies were appraised according to how the sites were selected for evaluation, the treatment used, and the study methodology. This Synthesis provides transportation professionals with a tool to help them make better decisions regarding the safety impacts of their traffic control treatments thereby contributing to the goal of Canada's Road Safety Vision – to make Canada's roads the safest in the world.