D.C. Mun. Regs. tit. 24 § 120
No unauthorized person shall loiter, walk, ride, drive, or otherwise trespass upon any of the following:
It shall be unlawful for any person or persons to remove snow from the tracks of any railway in the District of Columbia in a manner that obstructs the free passageway of any street, avenue, or roadway.
No person shall sprinkle salt or other decomposing substance upon any railway tracks or rails in the District of Columbia for the purpose of melting snow or ice on the tracks or rails, or for any purpose, unless a permit is granted by the Mayor.
No person, firm, or corporation shall move, cause to be moved, or take any part in moving a railway locomotive, car, or train of cars on or over an intersection at grade of that railway with any street, alley, avenue, highway, footway, sidewalk, parking, or other public space in the District, unless the movement is protected by a visible signal, such as a sign, red flag, or similarly suitable device, displayed at the intersection in advance of each movement by a member of the crew of the locomotive, car, or train.
If, in the opinion of the Mayor, the volume of pedestrian or vehicular traffic at any intersection at grade is sufficient to justify additional safeguards, the intersection shall, if ordered by the Mayor, be guarded also by a standard railway cross-arm warning sign, gate, electric bells, electric automatic flashing red signal lights, or other appliance, or combination of appliances, to be approved by the Mayor. The safeguarding appliances shall be constructed, operated, and maintained by and at the cost of the company operating the railway.
No person, firm, or corporation shall move, cause to be moved, or take part in moving a railway locomotive, car, or train of cars on or upon a street or other public space between sunset and sunrise, unless a headlight or other equivalent reflecting lantern, or a hand lantern in the hands of an attendant, is displayed upon the most advanced approaching part of the locomotive, car, or train or cars to give due warning of its approach to persons near or crossing the tracks.
No highway or railway crossing in the District of Columbia on which tracks of steam railroad are laid shall be obstructed by any train, locomotive, car, or crossing gates for a period longer than five (5) minutes; nor shall a train, locomotive, car, or cars be parked or stored on a street for an unreasonable time.
The supervisor of tracks or yardmaster shall be held liable and subject to prosecution for obstructions by crossing gates when, by his or her order, they are kept down for a longer time than is permitted by the rules of this chapter.
All railroad sidings, switches, and standing tracks within the District terminating at, abutting on, or adjacent to a street or other public space or private property, at whatever grade, shall at all times, without notice, when in use for the movement of cars, locomotives, or other railroad carriages, be protected and kept protected by the construction and maintenance of bumping blocks or other protection approved by the Mayor.
The person or persons, or corporation or corporations using the railroad sidings, switches, and standing tracks shall be responsible for the construction of the protection devices; and for maintaining them in sound, safe, and serviceable condition once they are approved by the Mayor.
D.C. Mun. Regs. Tit. 24, § 120