Guidelines for railroad preemption at signalized intersections.

This paper presents guidelines for preemption of traffic signal controllers near railroad grade crossings. The objective was to develop methods for determining when preemtion is required at isolated intersections and for specifying the duration of the preemption intervals. The guideline for preemption installation improves upon current recommendations. The timing procedure uses several assumptions concerning traffic behaviour on the approach crossing the tracks. Finally, queuing behaviour and track clearance times should be verified in the field after the design is implemented.