Tulsa is beginning to phase in new traffic signals with a flashing yellow arrow for permissive left turns. The first four of these new traffic signals will begin operating on Tuesday, Oct. 1, at the following intersections:
Also, soon to follow will be another flashing yellow arrow signal at West 71st Street and Tulsa Hills.
The flashing yellow arrow directs traffic in the left-turn lane in the same way as the green “ball,” which indicated that a driver must yield to oncoming traffic or pedestrians before turning left.
On these new traffic signals, the arrow for the left-turn lane will be either steady red, steady yellow, flashing yellow or steady green. “Red” will continue to mean “stop.” Steady yellow will mean “prepare to stop.” Flashing yellow will mean “proceed with left turn after yielding to oncoming traffic or pedestrians;” and green will mean “proceed with left turn.”
Signals with flashing yellow arrows for left turns have been included in the Manual on Uniform Traffic Control Devices since 2009, the version which Oklahoma adopted in 2012. The new signals improve traffic flow and safety. They are most helpful at intersections with frequent traffic congestion, high traffic volumes and above-average accident rates.
The National Cooperative Highway Research Program found the flashing yellow arrow to be highly effective at reducing driver confusion. It is seen as a low-cost measure that greatly improves motorist safety in urban areas. The yellow arrow provides a clear distinction between when turning vehicles are protected from oncoming traffic and when they must yield.