Safety And Guidelines For Protected/permissive Left-turn Controls At Signalized Intersections

Protected/permissive left-turn control is one of the three common types of signal control for left-turn traffic at signalized intersections, namely permissive-only or permitted-only (PM), protected-only (PT), and protected/permissive (P/P). This thesis is to analyze the safety aspects of protected/permissive left-turn control and give recommendations on selecting left-turn control types, especially those related to choosing between protected permissive and protected only.The conclusion is addressed by conducting a comprehensive literature review and a web-based agency survey. A synthesis of selecting left-turn control types will be suggested based on the results from the literature review and the agency survey with 36 responses considering various factors while making decision on selection of left-turn control types.