234.3—Application.
With the exception of § 234.11, this part applies to all railroads except:
(a)
A railroad that exclusively operates freight trains only on track which is not part of the general railroad system of transportation;
(b)
Rapid transit operations within an urban area that are not connected to the general railroad system of transportation; and
(c)
A railroad that operates passenger trains 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:
(4)
A common corridor with a railroad, i.e., its operations are within 30 feet of those of any railroad.
[75 FR 36558, June 28, 2010]