The placement of the sign "EXEMPT" on a crossing as outlined in the Manual on Uniform Traffic Control Devices (MUTCD) means;
"These supplemental signs inform drivers of vehicles carrying passengers for hire, school buses carrying students, or vehicles carrying hazardous materials that a stop is not required at certain designated highway-rail grade crossings, except when a train, locomotive, or other railroad equipment is approaching or occupying the highway-rail grade crossing, or the driver's view is blocked."
The MUTCD manual defines all signs permitted for use on public and private roadways...
I remember seeing a GP-7 or GP-9 parked just east of that crossing in the mid 1980's. I also remember seeing the back up from a train having crossed there one late night coming home from college around 1989. I think this got drilled in the middle of the night when traffic volumes were at their lightest.
The Morristown & Erie crossing at Troy Hills Road also has "Exempt" signs, again for the same reason. Prevents the multitude of school busses from having to stop at the crossing.
Chris V, traffic engineer
CV the Civil E