What must you do at a railroad crossing?

Certain vehicles are required to stop at railroad crossings even when no signals are warning of approaching trains. Such vehicles include school buses and trucks carrying hazardous materials such as explosives. Follow such vehicles at a safe distance and be prepared to stop. When you do arrive at a railroad crossing, obey all signs and signals. You must stop at a flashing red crossing signal, a lowered crossing gate, or a crossing signal whose bell is sounding. Do not cross until the flashing signal has stopped and the crossing gate has risen completely. Don't attempt to cross the tracks unless you have a clear path to the other side. Don't try to cut off or outrace an approaching train. A train traveling at 60 mph can take more than a mile to come to a complete stop. [Railroad Crossing Sign, Chapter 3 – Pavement Markings, Traffic Signs, Lights, and Signals, Missouri DOR Driver Guide; Railroad Crossing, Chapter 15 – Commercial Vehicles, Missouri DOR Driver Guide]