This report describes testing of prototype vehicle proximity alert system (VPAS) technologies, and presents and evaluates the results. The object was to determine the feasibility of VPAS for possible use in priority vehicles (i.e., emergency vehicles, school buses, vehicles carrying hazardous materials, and large trucks) to detect trains at highway-railroad grade crossings. VPAS can transmit visual and audible warnings to motorists. These warnings are designed to alert motorists in the vicinity of a grade crossing of the presence of a train approaching the crossing.