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Title 40

Displaying title 40, up to date as of 6/04/2026. Title 40 was last amended 6/04/2026.
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Title 40Protection of EnvironmentPart / Section
Chapter IEnvironmental Protection Agency1 – 1099
Subchapter CAir Programs50 – 99
Part 61National Emission Standards for Hazardous Air Pollutants61.01 – 61.359
Subpart AGeneral Provisions61.01 – 61.19
Subpart BNational Emission Standards for Radon Emissions From Underground Uranium Mines61.20 – 61.26
Subpart CNational Emission Standard for Beryllium61.30 – 61.34
Subpart DNational Emission Standard for Beryllium Rocket Motor Firing61.40 – 61.44
Subpart ENational Emission Standard for Mercury61.50 – 61.56
Subpart FNational Emission Standard for Vinyl Chloride61.60 – 61.71
Subpart G [Reserved]
Subpart HNational Emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities61.90 – 61.97
Subpart INational Emission Standards for Radionuclide Emissions From Federal Facilities Other Than Nuclear Regulatory Commission Licensees and Not Covered by Subpart H61.100 – 61.108
Subpart JNational Emission Standard for Equipment Leaks (Fugitive Emission Sources) of Benzene61.110 – 61.112
Subpart KNational Emission Standards for Radionuclide Emissions From Elemental Phosphorus Plants61.120 – 61.127
Subpart LNational Emission Standard for Benzene Emissions from Coke By-Product Recovery Plants61.130 – 61.139
Subpart MNational Emission Standard for Asbestos61.140 – 61.157
Subpart NNational Emission Standard for Inorganic Arsenic Emissions From Glass Manufacturing Plants61.160 – 61.165
Subpart ONational Emission Standard for Inorganic Arsenic Emissions From Primary Copper Smelters61.170 – 61.177
Subpart PNational Emission Standard for Inorganic Arsenic Emissions From Arsenic Trioxide and Metallic Arsenic Production Facilities61.180 – 61.186
Subpart QNational Emission Standards for Radon Emissions From Department of Energy Facilities61.190 – 61.193
Subpart RNational Emission Standards for Radon Emissions From Phosphogypsum Stacks61.200 – 61.210
Subpart S [Reserved]
Subpart TNational Emission Standards for Radon Emissions From the Disposal of Uranium Mill Tailings61.220 – 61.226
Subpart U [Reserved]
Subpart VNational Emission Standard for Equipment Leaks (Fugitive Emission Sources)61.240 – 61.247
Subpart WNational Emission Standards for Radon Emissions From Operating Mill Tailings61.250 – 61.256
Subpart X [Reserved]
Subpart YNational Emission Standard for Benzene Emissions From Benzene Storage Vessels61.270 – 61.277
Subparts Z-AA [Reserved]
Subpart BBNational Emission Standard for Benzene Emissions From Benzene Transfer Operations61.300 – 61.306
Subparts CC-EE [Reserved]
Subpart FFNational Emission Standard for Benzene Waste Operations61.340 – 61.359
Appendix A to Part 61
Appendix A to Part 61
Appendix B to Part 61
Test Methods
Appendix C to Part 61
Quality Assurance Procedures
Appendix D to Part 61
Methods for Estimating Radionuclide Emissions
Appendix E to Part 61
Compliance Procedures Methods for Determining Compliance With Subpart I