More bicycle traffic signals are appearing with traditional round red, yellow and green signals at intersections, reports USA Today.
Sixteen U.S. cities, including Austin, Denver, Minneapolis, San Francisco, Seattle and Washington D.C., have installed the lights, which use a bicycle-shaped signal, according to an October study commissioned by the Oregon Department of Transportation and the Federal Highway Administration.
According to the study, bicyclists can be at risk when entering an intersection on a yellow light, which may allow enough time for cars to clear the intersection, but not bikes.
Even green lights may not allow enough time for a bicyclist starting from a stopped position to make it across. Bicycle signals can help prevent collisions by giving the cyclist a few seconds head start.
Some bicycle signals stand alone, while others are incorporated into regular traffic signals. Some are timed, while others are activated when a bicyclist approaches the intersection.