Traffic signal priority strategies for transit: a review of selected experiences in the United States.

The Traffic Signal Priority Strategies (TSPSs) used to date in the United States have been varied, involving different technologies and policies, but generally implement some type of green extension and red truncation. Despite the fairly long history, there has not been an establishment of a standard strategy or system, and deployments have been relatively rare. In part, this may be due to the difficulty in gathering conclusive evidence on the impacts of TSPSs on other traffic, especially in light of the different strategies and situations under which they are operated. While the studies were able to note a significant reduction in bus travel time, the nature and extent of other impacts was not always clear. Further research is necessary to fully evaluate such impacts under different situations. For the covering abstract see ITRD E114174.