49 CFR 239.3 - Application.
(a) Except as provided in paragraph (b) of this section, this part applies to all:
(2) Railroads that provide commuter or other short-haul rail passenger train service in a metropolitan or suburban area (as described by 49 U.S.C. 20102(1)), including public authorities operating passenger train service; and
(b) This part does not apply to:
(1) Rapid transit operations in an urban area that are not connected with the general railroad system of transportation;
(2) Operation of private cars, including business/office cars and circus trains; or
(3) Tourist, scenic, historic, or excursion operations, whether on or off the general railroad system.