46 C.F.R. § 154.180
Contiguous hull structure: Welding procedure
Welding procedure tests for contiguous hull structure designed for a temperature colder than −18 °C (0 °F) must meet § 54.05-15 and subpart 57.03 of this chapter.
Welding procedure tests for contiguous hull structure designed for a temperature colder than −18 °C (0 °F) must meet § 54.05-15 and subpart 57.03 of this chapter.