Yellow trap

From Wikipedia, the free encyclopedia

The yellow trap is a potentially-dangerous scenario in traffic flow through a traffic light relating to permissive left turns. It occurs when a yellow light is displayed while, at the same time, oncoming traffic still has a green light, causing drivers to complete their left turn on yellow when it is not safe to do so.

As of March 2006, the US Department of Transportation is considering using a flashing yellow turn arrow, meaning that left turns are allowed but must yield to oncoming traffic. The flashing yellow turn arrow is displayed whenever oncoming traffic has a green light, eliminating the problem.

The City of Austin, Texas uses a special traffic light to protect left-turning vehicles caught in the yellow trap. The signal visible only to the left turn lane remains green (with a solid green, not an arrow, indicating turn when safe), even while the through traffic signal turns to yellow, then red. Thus traffic approaching from afar may see both green and red signals side by side, although the inappropriate signal disappears from view as the driver nears the intersection.

[edit] External links

• Fixing the Yellow Trap, Kittleson & Associates.
• Interim Approval for Optional Use of Flashing Yellow Arrow for Permissive Left Turns (IA-10) from the Manual on Uniform Traffic Control Devices.