(a) Except as provided in paragraph (b) of this section, this part applies to—

(1) Class I railroads;

(2) Railroads determined to have inadequate safety performance pursuant to § 271.13; and

(3) Railroads that voluntarily comply with the requirements of this part pursuant to § 271.15.

(b) This part does not apply to:

(1) Rapid transit operations in an urban area that are not connected to the general railroad system of transportation;

(2) Tourist, scenic, historic, or excursion operations, whether on or off the general railroad system of transportation;

(3) Operation of private cars, including business/office cars and circus trains;

(4) Railroads that operate only on track inside an installation that is not part of the general railroad system of transportation (i.e., plant railroads, as defined in § 271.5); and

(5) Commuter or intercity passenger railroads that are subject to Federal system safety program requirements contained in part 270 of this chapter.

(c) If a railroad contracts out significant portions of its operations, the contractor and the contractor's employees performing the railroad's operations shall be considered directly affected employees for purposes of this part.