Under Arizona law, you must stop at a railroad crossing when

Explanation

Under Arizona law, you must stop at a railroad crossing when (1) the crossing gates are lowered, (2) an electric or mechanical signal is warning of an approaching train, (3) a flagger is warning of an approaching train, (4) a train is sounding its horn or whistle (usually within 1,500 feet of the crossing), or (5) you observe a train approaching the crossing. Note: Don't just depend on the railroad crossing signals or gates to tell you when it's safe to proceed. They might be malfunctioning. Always look in both directions to see for yourself whether it's safe to cross.