Bicycle-Specific Traffic Signals: Results from State-of-the-Practice Review

This paper presents the results of a survey of North American jurisdictions with known installations of bicycle-specific traffic signals and a review of available engineering guidance. Surveys were sent to agencies in 21 jurisdictions (19 in the United States and two in Canada) that requested detailed engineering aspects of the signal design such as placement, mounting height, lens diameter, backplate color, type of actuation, interval times, use of louvers, and performance. We reviewed guidance documents produced by the National Association of City Transportation Officials (NACTO); American Association of State Highway and Transportation Officials (AASHTO); Transportation Association of Canada (TAC); the CROW design manual for bicycle traffic; and the Canadian, U.S. and Californian manuals on uniform traffic control devices. Responses were received for 63 intersections and 149 separate signal heads. The survey results highlight the current treatments and variations of similar designs. A subsequent review of the documents generally revealed consistent guidance with regard to the design of bicycle-specific traffic signals. The guidance on bicycle signals has grown substantially in recent years, and it is likely that there will be less variety in future designs.