Not So Mellow Yellow
By David A. Kolman
Have you heard about those six cities that installed red-light cameras, shortened the yellow light duration and collected profits from an increase in the number of traffic violations written?
The National Motorists Association reports that Chattanooga and Nashville, Tenn.; Dallas and Lubbock, Texas; Springfield, Mo.; and Union City, Calif., each shortened the length of time for the yellow light on traffic signals to below the minimum prescribed by law. The NMA believes that these are merely the cities that have been caught with fast yellows, and that there are plenty of others.
The Federal Highway Administration’s Manual on Uniform Traffic Control Devices (MUTCD) specifies that the duration of the yellow change interval should be between 3 and 6 seconds. If you not familiar with the MUTCD, it defines the standards used by road managers nationwide to install and maintain traffic control devices on all public streets, highways, bikeways and private roads open to public traffic.
It should be noted, however, that within this 3 to 6 second range recommended by Section 4D.10 of the MUTCD, jurisdictions are free to set yellow change interval timing based on their own policies or studies. As we all know, the objective of the yellow light is to serve as a warning to drivers that the traffic signal is about to turn red, so come to a safe stop prior to the stop line, or proceed through the intersection if too near the intersection to stop safely.
Studies have shown that red light cameras help reduce red light violations and decrease intersection crashes. That makes the roads safer – and that is a good thing. Adequate yellow signal timing is important, and state and local transportation engineers should know what timing works best for their intersections. However, changing the timing for the purpose of increasing revenue rather than advancing safety cannot be tolerated.
When I first started driving, my father shared a lot of his driving experience and wisdom with me. One of the things he taught me was to always stay alert, and when approaching a traffic signal, especially one with a stale green light, plan for what to do should the light change.
Those are rare driver behaviors these days what with all the cell-phoning and texting while driving that goes on. So why take the chance of giving even one second less reaction time for a light to change?