A FYA traffic signal head features a flashing yellow arrow indication in addition to red, yellow and green steady arrow indications. While the flashing yellow arrow indication is displayed, left-turns are permitted, but the motorist must first yield to oncoming traffic and pedestrians. Otherwise, the new traffic signals work the same as traditional signals. Flashing yellow arrow signals have been shown to help drivers make fewer mistakes.They keep motorists safer during heavy traffic and reduce delays when traffic is light. A national study demonstrated that drivers found flashing yellow left-turn arrows more understandable than traditional yield-on-green indications.The FYA was added as an optional configuration in the 2009 Manual on Uniform Traffic Control Devices (MUTCD) and is currently being used in a majority of states nationwide. As a result, there has been increased interest in implementing FYA for left-turn signal phasing within Pennsylvania.