Section 217.3 - Application(a) Except as provided in paragraph (b) of this section, this part applies to railroads that operate trains or other rolling equipment on standard gage track which is part of the general railroad system of transportation.(b) This part does not apply to-(1) A railroad that operates only on track inside an installation which is not part of the general railroad system of transportation; or(2) Rapid transit operations in an urban area that are not connected with the general railroad system of transportation.40 FR 2690, Jan. 15, 1975, as amended at 54 FR 33229, Aug. 14, 1989