Download or read book An Evaluation of Effectiveness of Flashing Yellow Arrow Signal for Left-turns written by Kailas Venkitasubramanian and published by . This book was released on 2008 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis evaluated the effectiveness of flashing yellow arrow (FYA) permitted left-turn signals in reducing conflicts and events at intersections. A FYA permissive signal is a recent treatment used as an alternate to circular green signal at signalized intersections. It is the newest addition to the series of permitted left-turn signal indicators and has been designed to improve the clarity of indication among drivers. The signal is expected to result in safer turning movements during the permitted phase. Conflict data was collected during morning peak period (7:00 AM to 9:00 AM) and evening peak period (4:00 PM to 8:00 PM) at four study intersections in Charlotte. Data was collected before the installation of FYA signal was introduced and after one month, three months and six months of installation of FYA. Relevant types of conflicts and events associated with left-turn maneuver were observed and recorded. Descriptive statistics, proportions of conflicts/events and statistical tests were conducted to analyze the data collected. Conflicts and events were also analyzed separately for each intersection using various comparison sets to understand their trend over time and the impact of FYA on them. Observations and analysis indicated that benefits in terms of reduction in conflicts and events are substantial at 7th Street / 5th Street intersection and Mallard Creek Church Road / 1-85 Southbound interchange but are marginal and currently statistically insignificant at Sunset Road / 1-77 interchanges. Overall, FYA leaves a positive effect on the intersection safety, helps reduce vehicular conflicts/events and is suitable for application at other intersections in the future.