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Title: Guidelines for the use of protected/permissive left-turn phasing

Journal Article · · ITE J.; (United States)
OSTI ID:6170728

Turning left across opposing traffic at a signalized intersection could result in a traffic accident, as well as create motorist delay. A solution to the left-turn problem may be the addition of a left-turn phase when certain guidelines are met. After a decision has been made to add a left-turn phase, one of two basic alternative phasing methods is . In a previous research study, the results of replacing protected-only (exclusive) with protected/permissive (permissive) phasing at four trial intersections were studied. The permissive phasing provided a substantial reduction in delay and was popular with local drivers. However, several left-turn related accidents occurred at those locations. Since those initial trial installations, permissive phasing has been used at several intersections across the state. This created a larger data base that could be used to determine when permissive phasing could be used without causing an accident problem. The objective of this study was to develop guidelines to aid traffic engineers in deciding whether permissive left-turn phasing is appropriate for use at a given location.

Research Organization:
Univ. of Kentucky Transportation Research Program
OSTI ID:
6170728
Journal Information:
ITE J.; (United States), Vol. 57:7
Country of Publication:
United States
Language:
English