49 C.F.R. § 178.338-6 Manholes.
Title 49 - Transportation
(a) Each tank in oxygen service must be provided with a manhole as prescribed in Section VIII of the ASME Code (IBR, see §171.7 of this subchapter). (b) Each tank having a manhole must be provided with a means of entrance and exit through the jacket, or the jacket must be marked to indicate the manway location on the tank. (c) A manhole with a bolted closure may not be located on the front head of the tank. [Amdt. 178–77, 48 FR 27704, June 16, 1983, as amended at 49 FR 24316, June 12, 1984; 68 FR 75754, Dec. 31, 2003]
Title 49: Transportation
PART 178—SPECIFICATIONS FOR PACKAGINGS
Subpart J—Specifications for Containers for Motor Vehicle Transportation
§ 178.338-6 Manholes.