Site Feedback

Title 40

Displaying title 40, up to date as of 3/06/2024. Title 40 was last amended 3/06/2024.
There have been changes in the last two weeks to Part 63.
eCFR Content

The Code of Federal Regulations (CFR) is the official legal print publication containing the codification of the general and permanent rules published in the Federal Register by the departments and agencies of the Federal Government. The Electronic Code of Federal Regulations (eCFR) is a continuously updated online version of the CFR. It is not an official legal edition of the CFR.

Learn more about the eCFR, its status, and the editorial process.

Title 40Protection of EnvironmentPart / Section
Chapter IEnvironmental Protection Agency1 – 1099
Subchapter CAir Programs50 – 99
Part 63National Emission Standards for Hazardous Air Pollutants for Source Categories63.1 – 63.12099
Subpart AGeneral Provisions63.1 – 63.16
Subpart BRequirements for Control Technology Determinations for Major Sources in Accordance With Clean Air Act Sections, Sections 112(g) and 112(j)63.40 – 63.56
Subpart CList of Hazardous Air Pollutants, Petitions Process, Lesser Quantity Designations, Source Category List63.60 – 63.69
Subpart DRegulations Governing Compliance Extensions for Early Reductions of Hazardous Air Pollutants63.70 – 63.81
Subpart EApproval of State Programs and Delegation of Federal Authorities63.90 – 63.99
Subpart FNational Emission Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical Manufacturing Industry63.100 – 63.107
Subpart GNational Emission Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical Manufacturing Industry for Process Vents, Storage Vessels, Transfer Operations, and Wastewater63.110 – 63.153
Subpart HNational Emission Standards for Organic Hazardous Air Pollutants for Equipment Leaks63.160 – 63.183
Subpart INational Emission Standards for Organic Hazardous Air Pollutants for Certain Processes Subject to the Negotiated Regulation for Equipment Leaks63.190 – 63.193
Subpart JNational Emission Standards for Hazardous Air Pollutants for Polyvinyl Chloride and Copolymers Production63.210 – 63.217
Subpart K [Reserved]
Subpart LNational Emission Standards for Coke Oven Batteries63.300 – 63.313
Subpart MNational Perchloroethylene Air Emission Standards for Dry Cleaning Facilities63.320 – 63.326
Subpart NNational Emission Standards for Chromium Emissions From Hard and Decorative Chromium Electroplating and Chromium Anodizing Tanks63.340 – 63.348
Subpart OEthylene Oxide Emissions Standards for Sterilization Facilities63.360 – 63.368
Subpart P [Reserved]
Subpart QNational Emission Standards for Hazardous Air Pollutants for Industrial Process Cooling Towers63.400 – 63.407
Subpart RNational Emission Standards for Gasoline Distribution Facilities (Bulk Gasoline Terminals and Pipeline Breakout Stations)63.420 – 63.429
Subpart SNational Emission Standards for Hazardous Air Pollutants from the Pulp and Paper Industry63.440 – 63.459
Subpart TNational Emission Standards for Halogenated Solvent Cleaning63.460 – 63.471
Subpart UNational Emission Standards for Hazardous Air Pollutant Emissions: Group I Polymers and Resins63.480 – 63.507
Subpart V [Reserved]
Subpart WNational Emission Standards for Hazardous Air Pollutants for Epoxy Resins Production and Non-Nylon Polyamides Production63.520 – 63.529
Subpart XNational Emission Standards For Hazardous Air Pollutants From Secondary Lead Smelting63.541 – 63.552
Subpart YNational Emission Standards for Marine Tank Vessel Loading Operations63.560 – 63.568
Subpart Z [Reserved]
§§ 63.569-63.599 [Reserved]
Subpart AANational Emission Standards for Hazardous Air Pollutants from Phosphoric Acid Manufacturing Plants63.600 – 63.611
Subpart BBNational Emission Standards for Hazardous Air Pollutants from Phosphate Fertilizers Production Plants63.620 – 63.632
Subpart CCNational Emission Standards for Hazardous Air Pollutants From Petroleum Refineries63.640 – 63.679
Subpart DDNational Emission Standards for Hazardous Air Pollutants from Off-Site Waste and Recovery Operations63.680 – 63.698
Subpart EENational Emission Standards for Magnetic Tape Manufacturing Operations63.701 – 63.708
Subpart FF [Reserved]
Subpart GGNational Emission Standards for Aerospace Manufacturing and Rework Facilities63.741 – 63.759
Subpart HHNational Emission Standards for Hazardous Air Pollutants From Oil and Natural Gas Production Facilities63.760 – 63.779
Subpart IINational Emission Standards for Shipbuilding and Ship Repair (Surface Coating)63.780 – 63.789
Subpart JJNational Emission Standards for Wood Furniture Manufacturing Operations63.800 – 63.819
Subpart KKNational Emission Standards for the Printing and Publishing Industry63.820 – 63.839
Subpart LLNational Emission Standards for Hazardous Air Pollutants for Primary Aluminum Reduction Plants63.840 – 63.859
Subpart MMNational Emission Standards for Hazardous Air Pollutants for Chemical Recovery Combustion Sources at Kraft, Soda, Sulfite, and Stand-Alone Semichemical Pulp Mills63.860 – 63.868
Subpart NNNational Emission Standards for Hazardous Air Pollutants for Wool Fiberglass Manufacturing at Area Sources63.880 – 63.899
Subpart OONational Emission Standards for Tanks—Level 163.900 – 63.908
Subpart PPNational Emission Standards for Containers63.920 – 63.929
Subpart QQNational Emission Standards for Surface Impoundments63.940 – 63.949
Subpart RRNational Emission Standards for Individual Drain Systems63.960 – 63.967
Subpart SSNational Emission Standards for Closed Vent Systems, Control Devices, Recovery Devices and Routing to a Fuel Gas System or a Process63.980 – 63.999
Subpart TTNational Emission Standards for Equipment Leaks—Control Level 163.1000 – 63.1018
Subpart UUNational Emission Standards for Equipment Leaks—Control Level 2 Standards63.1019 – 63.1039
Subpart VVNational Emission Standards for Oil-Water Separators and Organic-Water Separators63.1040 – 63.1050
Subpart WWNational Emission Standards for Storage Vessels (Tanks)—Control Level 263.1060 – 63.1067
Subpart XXNational Emission Standards for Ethylene Manufacturing Process Units: Heat Exchange Systems and Waste Operations63.1080 – 63.1097
Subpart YYNational Emission Standards for Hazardous Air Pollutants for Source Categories: Generic Maximum Achievable Control Technology Standards63.1100 – 63.1114
Subparts ZZ–BBB [Reserved]
Subpart CCCNational Emission Standards for Hazardous Air Pollutants for Steel Pickling—HCl Process Facilities and Hydrochloric Acid Regeneration Plants63.1155 – 63.1174
Subpart DDDNational Emission Standards for Hazardous Air Pollutants for Mineral Wool Production63.1175 – 63.1199
Subpart EEENational Emission Standards for Hazardous Air Pollutants from Hazardous Waste Combustors63.1200 – 63.1221
Subpart FFF [Reserved]
Subpart GGGNational Emission Standards for Pharmaceuticals Production63.1250 – 63.1261
Subpart HHHNational Emission Standards for Hazardous Air Pollutants From Natural Gas Transmission and Storage Facilities63.1270 – 63.1289
Subpart IIINational Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production63.1290 – 63.1309
Subpart JJJNational Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins63.1310 – 63.1336
Subpart KKK [Reserved]
Subpart LLLNational Emission Standards for Hazardous Air Pollutants From the Portland Cement Manufacturing Industry63.1340 – 63.1359
Subpart MMMNational Emission Standards for Hazardous Air Pollutants for Pesticide Active Ingredient Production63.1360 – 63.1369
Subpart NNNNational Emission Standards for Hazardous Air Pollutants for Wool Fiberglass Manufacturing63.1380 – 63.1399
Subpart OOONational Emission Standards for Hazardous Air Pollutant Emissions: Manufacture of Amino/Phenolic Resins63.1400 – 63.1419
Subpart PPPNational Emission Standards for Hazardous Air Pollutant Emissions for Polyether Polyols Production63.1420 – 63.1439
Subpart QQQNational Emission Standards for Hazardous Air Pollutants for Primary Copper Smelting63.1440 – 63.1459
Subpart RRRNational Emission Standards for Hazardous Air Pollutants for Secondary Aluminum Production63.1500 – 63.1520
Subpart SSS [Reserved]
Subpart TTTNational Emission Standards for Hazardous Air Pollutants for Primary Lead Smelting63.1541 – 63.1551
Subpart UUUNational Emission Standards for Hazardous Air Pollutants for Petroleum Refineries: Catalytic Cracking Units, Catalytic Reforming Units, and Sulfur Recovery Units63.1560 – 63.1579
Subpart VVVNational Emission Standards for Hazardous Air Pollutants: Publicly Owned Treatment Works63.1580 – 63.1595
Subpart WWW [Reserved]
Subpart XXXNational Emission Standards for Hazardous Air Pollutants for Ferroalloys Production: Ferromanganese and Silicomanganese63.1620 – 63.1679
Subpart AAAANational Emission Standards for Hazardous Air Pollutants: Municipal Solid Waste Landfills63.1930 – 63.1990
Subpart BBBB [Reserved]
Subpart CCCCNational Emission Standards for Hazardous Air Pollutants: Manufacturing of Nutritional Yeast63.2130 – 63.2192
Subpart DDDDNational Emission Standards for Hazardous Air Pollutants: Plywood and Composite Wood Products63.2230 – 63.2292
Subpart EEEENational Emission Standards for Hazardous Air Pollutants: Organic Liquids Distribution (Non-Gasoline)63.2330 – 63.2406
Subpart FFFFNational Emission Standards for Hazardous Air Pollutants: Miscellaneous Organic Chemical Manufacturing63.2430 – 63.2550
Subpart GGGGNational Emission Standards for Hazardous Air Pollutants: Solvent Extraction for Vegetable Oil Production63.2830 – 63.2872
Subpart HHHHNational Emission Standards for Hazardous Air Pollutants for Wet-Formed Fiberglass Mat Production63.2980 – 63.3079
Subpart IIIINational Emission Standards for Hazardous Air Pollutants: Surface Coating of Automobiles and Light-Duty Trucks63.3080 – 63.3176
Subpart JJJJNational Emission Standards for Hazardous Air Pollutants: Paper and Other Web Coating63.3280 – 63.3420
Subpart KKKKNational Emission Standards for Hazardous Air Pollutants: Surface Coating of Metal Cans63.3480 – 63.3561
Subpart MMMMNational Emission Standards for Hazardous Air Pollutants for Surface Coating of Miscellaneous Metal Parts and Products63.3880 – 63.3981
Subpart NNNNNational Emission Standards for Hazardous Air Pollutants: Surface Coating of Large Appliances63.4080 – 63.4181
Subpart OOOONational Emission Standards for Hazardous Air Pollutants: Printing, Coating, and Dyeing of Fabrics and Other Textiles63.4280 – 63.4371
Subpart PPPPNational Emission Standards for Hazardous Air Pollutants for Surface Coating of Plastic Parts and Products63.4480 – 63.4581
Subpart QQQQNational Emission Standards for Hazardous Air Pollutants: Surface Coating of Wood Building Products63.4680 – 63.4781
Subpart RRRRNational Emission Standards for Hazardous Air Pollutants: Surface Coating of Metal Furniture63.4880 – 63.4981
Subpart SSSSNational Emission Standards for Hazardous Air Pollutants: Surface Coating of Metal Coil63.5080 – 63.5209
Subpart TTTTNational Emission Standards for Hazardous Air Pollutants for Leather Finishing Operations63.5280 – 63.5460
Subpart UUUUNational Emission Standards for Hazardous Air Pollutants for Cellulose Products Manufacturing63.5480 – 63.5610
Subpart VVVVNational Emission Standards for Hazardous Air Pollutants for Boat Manufacturing63.5680 – 63.5779
Subpart WWWWNational Emissions Standards for Hazardous Air Pollutants: Reinforced Plastic Composites Production63.5780 – 63.5935
Subpart XXXXNational Emissions Standards for Hazardous Air Pollutants: Rubber Tire Manufacturing63.5980 – 63.6015
Subpart YYYYNational Emission Standards for Hazardous Air Pollutants for Stationary Combustion Turbines63.6080 – 63.6175
Subpart ZZZZNational Emissions Standards for Hazardous Air Pollutants for Stationary Reciprocating Internal Combustion Engines63.6580 – 63.6675
Subpart AAAAANational Emission Standards for Hazardous Air Pollutants for Lime Manufacturing Plants63.7080 – 63.7143
Subpart BBBBBNational Emission Standards for Hazardous Air Pollutants for Semiconductor Manufacturing63.7180 – 63.7195
Subpart CCCCCNational Emission Standards for Hazardous Air Pollutants for Coke Ovens: Pushing, Quenching, and Battery Stacks63.7280 – 63.7352
Subpart DDDDDNational Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial, Commercial, and Institutional Boilers and Process Heaters63.7480 – 63.7575
Subpart EEEEENational Emission Standards for Hazardous Air Pollutants for Iron and Steel Foundries63.7680 – 63.7765
Subpart FFFFFNational Emission Standards for Hazardous Air Pollutants for Integrated Iron and Steel Manufacturing Facilities63.7780 – 63.7852
Subpart GGGGGNational Emission Standards for Hazardous Air Pollutants: Site Remediation63.7880 – 63.7957
Subpart HHHHHNational Emission Standards for Hazardous Air Pollutants: Miscellaneous Coating Manufacturing63.7980 – 63.8105
Subpart IIIIINational Emission Standards for Hazardous Air Pollutants for Mercury Cell Chlor-Alkali Plants63.8180 – 63.8266
Subpart JJJJJNational Emission Standards for Hazardous Air Pollutants for Brick and Structural Clay Products Manufacturing63.8380 – 63.8515
Subpart KKKKKNational Emission Standards for Hazardous Air Pollutants for Clay Ceramics Manufacturing63.8530 – 63.8665
Subpart LLLLLNational Emission Standards for Hazardous Air Pollutants: Asphalt Processing and Asphalt Roofing Manufacturing63.8680 – 63.8698
Subpart MMMMMNational Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations63.8780 – 63.8830
Subpart NNNNNNational Emission Standards for Hazardous Air Pollutants: Hydrochloric Acid Production63.8980 – 63.9075
Subpart OOOOO [Reserved]
Subpart PPPPPNational Emission Standards for Hazardous Air Pollutants for Engine Test Cells/Stands63.9280 – 63.9375
Subpart QQQQQNational Emission Standards for Hazardous Air Pollutants for Friction Materials Manufacturing Facilities63.9480 – 63.9579
Subpart RRRRRNational Emission Standards for Hazardous Air Pollutants: Taconite Iron Ore Processing63.9580 – 63.9652
Subpart SSSSSNational Emission Standards for Hazardous Air Pollutants for Refractory Products Manufacturing63.9780 – 63.9824
Subpart TTTTTNational Emissions Standards for Hazardous Air Pollutants for Primary Magnesium Refining63.9880 – 63.9942
Subpart UUUUUNational Emission Standards for Hazardous Air Pollutants: Coal- and Oil-Fired Electric Utility Steam Generating Units63.9980 – 63.10042
Subpart VVVVV [Reserved]
Subpart WWWWWNational Emission Standards for Hospital Ethylene Oxide Sterilizers63.10382 – 63.10448
Subpart XXXXX [Reserved]
Subpart YYYYYNational Emission Standards for Hazardous Air Pollutants for Area Sources: Electric Arc Furnace Steelmaking Facilities63.10680 – 63.10692
Subpart ZZZZZNational Emission Standards for Hazardous Air Pollutants for Iron and Steel Foundries Area Sources63.10880 – 63.10906
Subpart AAAAAA [Reserved]
Subpart BBBBBBNational Emission Standards for Hazardous Air Pollutants for Source Category: Gasoline Distribution Bulk Terminals, Bulk Plants, and Pipeline Facilities63.11080 – 63.11100
Subpart CCCCCCNational Emission Standards for Hazardous Air Pollutants for Source Category: Gasoline Dispensing Facilities63.11110 – 63.11132
Subpart DDDDDDNational Emission Standards for Hazardous Air Pollutants for Polyvinyl Chloride and Copolymers Production Area Sources63.11140 – 63.11145
Subpart EEEEEENational Emission Standards for Hazardous Air Pollutants for Primary Copper Smelting Area Sources63.11146 – 63.11152
Subpart FFFFFFNational Emission Standards for Hazardous Air Pollutants for Secondary Copper Smelting Area Sources63.11153 – 63.11159
Subpart GGGGGGNational Emission Standards for Hazardous Air Pollutants for Primary Nonferrous Metals Area Sources—Zinc, Cadmium, and Beryllium63.11160 – 63.11168
Subpart HHHHHHNational Emission Standards for Hazardous Air Pollutants: Paint Stripping and Miscellaneous Surface Coating Operations at Area Sources63.11169 – 63.11180
Subpart IIIIII [Reserved]
Subpart JJJJJJNational Emission Standards for Hazardous Air Pollutants for Industrial, Commercial, and Institutional Boilers Area Sources63.11193 – 63.11237
Subpart KKKKKK [Reserved]
Subpart LLLLLLNational Emission Standards for Hazardous Air Pollutants for Acrylic and Modacrylic Fibers Production Area Sources63.11393 – 63.11399
Subpart MMMMMMNational Emission Standards for Hazardous Air Pollutants for Carbon Black Production Area Sources63.11400 – 63.11406
Subpart NNNNNNNational Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources: Chromium Compounds63.11407 – 63.11413
Subpart OOOOOONational Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production and Fabrication Area Sources63.11414 – 63.11420
Subpart PPPPPPNational Emission Standards for Hazardous Air Pollutants for Lead Acid Battery Manufacturing Area Sources63.11421 – 63.11427
Subpart QQQQQQNational Emission Standards for Hazardous Air Pollutants for Wood Preserving Area Sources63.11428 – 63.11434
Subpart RRRRRRNational Emission Standards for Hazardous Air Pollutants for Clay Ceramics Manufacturing Area Sources63.11435 – 63.11447
Subpart SSSSSSNational Emission Standards for Hazardous Air Pollutants for Glass Manufacturing Area Sources63.11448 – 63.11461
Subpart TTTTTTNational Emission Standards for Hazardous Air Pollutants for Secondary Nonferrous Metals Processing Area Sources63.11462 – 63.11474
Subpart UUUUUU [Reserved]
Subpart VVVVVVNational Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources63.11494 – 63.11503
Subpart WWWWWWNational Emission Standards for Hazardous Air Pollutants: Area Source Standards for Plating and Polishing Operations63.11504 – 63.11513
Subpart XXXXXXNational Emission Standards for Hazardous Air Pollutants Area Source Standards for Nine Metal Fabrication and Finishing Source Categories63.11514 – 63.11523
Subpart YYYYYYNational Emission Standards for Hazardous Air Pollutants for Area Sources: Ferroalloys Production Facilities63.11524 – 63.11543
Subpart ZZZZZZNational Emission Standards for Hazardous Air Pollutants: Area Source Standards for Aluminum, Copper, and Other Nonferrous Foundries63.11544 – 63.11558
Subpart AAAAAAANational Emission Standards for Hazardous Air Pollutants for Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing63.11559 – 63.11567
Subpart BBBBBBBNational Emission Standards for Hazardous Air Pollutants for Area Sources: Chemical Preparations Industry63.11579 – 63.11588
Subpart CCCCCCCNational Emission Standards for Hazardous Air Pollutants for Area Sources: Paints and Allied Products Manufacturing63.11599 – 63.11618
Subpart DDDDDDDNational Emission Standards for Hazardous Air Pollutants for Area Sources: Prepared Feeds Manufacturing63.11619 – 63.11638
Subpart EEEEEEENational Emission Standards for Hazardous Air Pollutants: Gold Mine Ore Processing and Production Area Source Category63.11640 – 63.11653
Subparts FFFFFFF and GGGGGGG [Reserved]
Subpart HHHHHHHNational Emission Standards for Hazardous Air Pollutant Emissions for Polyvinyl Chloride and Copolymers Production63.11860 – 63.12099
Appendix A to Part 63
Test Methods
Appendix B to Part 63
Sources Defined for Early Reduction Provisions
Appendix C to Part 63
Determination of the Fraction Biodegraded (Fbio) in a Biological Treatment Unit
Appendix D to Part 63
Alternative Validation Procedure for EPA Waste and Wastewater Methods
Appendix E to Part 63
Monitoring Procedure for Nonthoroughly Mixed Open Biological Treatment Systems at Kraft Pulp Mills Under Unsafe Sampling Conditions