Improved Highway–Railway Interface for the Preempt Trap

Railroad preemption is intended to improve safety at highway–railway intersections by minimizing the likelihood that a vehicle will become trapped on the crossing. However, unless sufficient time is provided to transfer right-of-way safely from the currently operating highway traffic phase, preemption can cause safety problems for highway users. Advance preemption has been used to address right-of-way transfer time issues without making the railroad warning time excessively long. The use of advance preemption without proper precautions can lead to the preempt trap. A new approach that uses improved communication has been developed and implemented to address the needs of all users at and near the highway–railway intersection. The results of a field implementation in Los Angeles, California, demonstrate the effectiveness of the new approach.