US lawFederal (United States)RegulationsTitle 40 CFR — Protection of EnvironmentChapter I — ENVIRONMENTAL PROTECTION AGENCYPart 57 — PRIMARY NONFERROUS SMELTER ORDERSSubpart A — General57.10640 C.F.R. § 57.106Expiration date.Last amended: 2016Year: 2026Length: 20 wordsOfficial source Cite as 40 C.F.R. § 57.106 (2026)Each NSO shall state its expiration date. No NSO issued under this regulation shall expire later than January 1, 1988.Previous40 C.F.R. § 57.105Next40 C.F.R. § 57.107