Why do side streets not have flashing lights for their school zone signs?
Beacons serve a useful purpose where the flashing light is used to alert drivers of unusual conditions that are not readily apparent, such as obstructions in the roadway, uncommon roadway conditions, narrow bridges, or unusual conditions hidden from motorists’ view. At intersections, the MUTCD states: “Beacons are intended for use . . . where traffic or physical condition do not justify conventional traffic signals but where high crash rates indicate a special hazard.” For any beacon to be effective, it must command the respect of the motoring public. In other words, immediately after seeing the beacon, the driver must consistently see an unusual condition that is being singled out for attention. Furthermore, the motorist should view the condition as serious enough to justify the special treatment provided by the beacon. When beacons are used improperly or installed at too many locations they soon lose much of their effectiveness. They simply cease to command the respect of the drivers
