The phrase "grade crossings" refers to the places where a road or path intersects with a railway track. It means the spot where vehicles or pedestrians can cross the train tracks on the same level. Full definition
It is a «one stop shop» for readers who want to learn more about the critical importance of rail grade crossing safety. (fmcsa.dot.gov)
At least 120 days for 3 serious violations or 2 violations of a law that regulates the operation of a motor vehicle at a railroad grade crossing within a period of 3 years. (dmv.org)
At least 1 year if you're convicted of 3 violations of a law that regulates the operation of a motor vehicle at a railroad grade crossing within a period of 3 years. (dmv.org)