49 CFR §230.2

1. (a)Except as provided in paragraph (b) of this section, this part applies to all railroads that operate steam locomotives.
2. (b)This part does not apply to:
   1. (1)A railroad with track gage of less than 24 inches;
   2. (2)A railroad that operates exclusively freight trains and does so only on track inside an installation that is not part of the general system of transportation;
   3. (3)Rapid transit operations in an urban area that are not connected to the general system of transportation; or
   4. (4)A railroad that operates passenger trains and does so only on track inside an installation that is insular, i.e., its operations are limited to a separate enclave in such a way that there is no reasonable expectation that the safety of the public—except a business guest, a licensee of the railroad or an affiliated entity, or a trespasser—would be affected by the operation. An operation will not be considered insular if one or more of the following exists on its line:
      1. (i)A public highway-rail crossing that is in use;
      2. (ii)An at-grade rail crossing that is in use;
      3. (iii)A bridge over a public road or waters used for commercial navigation; or
      4. (iv)A common corridor with another railroad, i.e., its operations are conducted within 30 feet of those of any other railroad.
3. (c)See appendix A of part 209 for a current statement of the FRA's policy on its exercise of jurisdiction.