Code of Federal Regulations Title 40, Volume 6, July 1, 2017 contains regulations governing Protection of Environment and may also be referenced as: - Code of Federal Regulations Title 40, Volume 6, July 1, 2017 - CFR Title 40 - CFR 40, Protection of Environment - CFR 40, Parts 53 to 59, Protection of Environment This volume contains Parts 53 to 59: - Part 53; AMBIENT AIR MONITORING REFERENCE AND EQUIVALENT METHODS - Part 54; PRIOR NOTICE OF CITIZEN SUITS - Part 55; OUTER CONTINENTAL SHELF AIR REGULATIONS - Part 56; REGIONAL CONSISTENCY - Part 57; PRIMARY NONFERROUS SMELTER ORDERS - Part 58; AMBIENT AIR QUALITY SURVEILLANCE - Part 59; NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS