49 C.F.R. § 193.2321 Nondestructive tests.
Title 49 - Transportation
The butt welds in metal shells of storage tanks with internal design pressure above 15 psig must be radiographically tested in accordance with the ASME Boiler and Pressure Vessel Code (Section VIII Division 1), except that hydraulic load bearing shells with curved surfaces that are subject to cryogenic temperatures, 100 percent of both longitudinal (or meridional) and circumferential (or latitudinal) welds must be radiographically tested. [Amdt. 193–17, 65 FR 10960, Mar. 1, 2000]
Title 49: Transportation
PART 193—LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS
Subpart D—Construction
§ 193.2321 Nondestructive tests.