Q: I have noticed that traffic lights give a very brief flash of white light right before turning red. It is right after the yellow starts fading and right before the red comes on.
It flashes out of the spot where the red is (top spot). Some lights are much more noticeable than others. Am I seeing things?
I only can guess that if it is a flash, it is designed to get your attention to the light turning red, but I have never heard of people talking about this.
I have asked people if they have seen it before, and they all say no, but when pointed out, they do see it. So what’s up?
Travis Schuermann, Everett
A: Wayne Wentz, city of Everett traffic engineer, said in 1999, as an energy-saving measure, Everett replaced red incandescent lamps in signals with lamps consisting of an array of light-emitting diodes, or LEDs.
"The particular lamps we use produce a flash of brightness (red, not white) at the beginning of the red," Wentz said. "This was not a feature planned by the manufacturer of the lamps, but it does not decrease the life of the lamps nor violate any standards."
If anything, Wentz said, it may alert some inattentive drivers the light has turned red, thus preventing collisions.
"If this flash helps to reduce red light running, we traffic engineers have no objection," he said.
"By the way, we not only save in energy and lamp replacement costs, but for 10 years we will receive a rebate from Bonneville Power Administration for our reduced demand. Total cost savings and rebates come to about $40,000 a year."
Have a question about traffic or street rules around Snohomish and Island counties? We can help find an answer. Send questions by fax to 425-339-3435; e-mail to newstips@heraldnet.com; or address to Street Smarts, P.O. Box 930, Everett, WA 98206. Include your name and phone number.
Talk to us
> Give us your news tips.
> Send us a letter to the editor.
> More Herald contact information.
