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Flashing Beacons

Warning of hazards ahead
Flashing beacons (sometimes called flashers or flashing lights) are frequently requested because folks believe that they will slow down traffic. However, the real purpose of flashers is to attract attention to unexpected hazards.

What are the appropriate conditions for flashing lights?
A flashing beacon is a very effective device for warning of unexpected or hazardous conditions not readily visible to drivers. One of the more common locations where flashers are effective is above a stop sign controlled intersection, located just beyond a curve, hidden from the view of approaching motorists.

Is there a flip side, perhaps a situation where a flasher should not be used?
Immediately after seeing a flasher, drivers must consistently see an unusual condition which requires special attention. The condition must be perceived as serious enough to justify special attention. For any traffic control device to be effective, it must command the respect of motorists. If it seems arbitrary or unnecessary, drivers tend to ignore it.

Then there are problems associated with the installation of unnecessary flashers?
Unwarranted flashing beacons tend to lose much of their effectiveness. After continually being alerted to a condition which does not appear to be truly unusual, research has shown that drivers stop 'seeing' the flashing beacon. This can result in a disregard for all beacons, even those that are truly needed.

If I think there is a problem and a flashing beacon isn't the answer, what
should I do?

Contact the appropriate public agency, WSDOT regarding state highways, or your city or county public works department regarding local roadways. Ask the traffic engineers to look at the situation. Ask them about lesser forms of traffic control that might apply. When requesting a flashing beacon, don't be surprised if the traffic engineer seems skeptical or difficult to convince; it's for good reason. It is essential to prove that there is a problem which can be solved by installing a flashing beacon before one should be installed. It is of the utmost importance that flashing beacons be kept to a minimum if a high degree of respect is to be maintained for flashers that are truly needed.