49 CFR §213.347

1. (a)There shall be no at-grade (level) highway crossings, public or private, or rail-to-rail crossings at-grade on Class 8 and 9 track.
2. (b)If train operation is projected at Class 7 speed for a track segment that will include rail-highway grade crossings, the track owner shall submit for FRA's approval a complete description of the proposed warning/barrier system to address the protection of highway traffic and high speed trains. Trains shall not operate at Class 7 speeds over any track segment having highway-rail grade crossings unless:
   1. (1)An FRA-approved warning/barrier system exists on that track segment; and
   2. (2)All elements of that warning/barrier system are functioning.