US lawFederal (United States)RegulationsTitle 46 CFR — ShippingChapter I — COAST GUARD, DEPARTMENT OF HOMELAND SECURITYPart 64 — MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMSSubpart B — Standards for an MPT64.4146 C.F.R. § 64.41Stop valve closure.Last amended: 2016Year: 2026Length: 15 wordsOfficial source Cite as 46 C.F.R. § 64.41 (2026)A stop valve that operates by a screwed spindle must close in a clockwise direction.Previous46 C.F.R. § 64.39Next46 C.F.R. § 64.43