(a) Scope. (1) Railroads. Consistent with its statutory authority, the NTSB is responsible for the investigation of railroad accidents, collisions, crashes, derailments, explosions, incidents, and releases in which there is a fatality, substantial property damage, or which involve a passenger train, as described in part 840 of this chapter.

(2) Pipelines. The NTSB is responsible for the investigation of pipeline accidents, explosions, incidents, and ruptures in which there is a fatality, significant injury to the environment, or substantial property damage. This excludes accidents involving pipelines only carrying water or sewage.

(3) Hazardous Materials. The NTSB is responsible for evaluating the adequacy of safeguards and procedures for the transportation of hazardous materials, and the performance of other entities of the Federal government responsible for the safe transportation of hazardous materials. Such evaluations may take place as part of the investigation of a transportation accident subject to the NTSB's authority and include applicable regulations in other subparts of this part.

(b) Authority to examine or test. Pursuant to § 831.9 of this part, during an investigation, a credentialed employee of the NTSB is authorized to examine or test any rolling stock, track, or pipeline component, or any part of any such item (or contents therein) when such examination or testing is determined to be required for purposes of such investigation. Examination or testing will be conducted—

(1) To the extent practicable, so as to not interfere with or obstruct the transportation services provided by the owner or operator of such rolling stock, track, signal, rail shop, property, or pipeline component; and

(2) In a manner that preserves evidence relating to the transportation accident consistent with the needs of the investigation.