US lawFederal (United States)RegulationsTitle 46 CFR — ShippingChapter I — COAST GUARD, DEPARTMENT OF HOMELAND SECURITYPart 30 — GENERAL PROVISIONSSubpart 30.10—Definitions30.10-5546 C.F.R. § 30.10-55Pressure vacuum relief valve—TB/ALL.Last amended: 2016Year: 2026Length: 31 wordsOfficial source Cite as 46 C.F.R. § 30.10-55 (2026)The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in enclosed places.Previous46 C.F.R. § 30.10-50Next46 C.F.R. § 30.10-57