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Title 40

Displaying title 40, up to date as of 4/17/2024. Title 40 was last amended 4/17/2024.
There have been changes in the last two weeks to Subchapter C.
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Title 40Protection of EnvironmentPart / Section
Chapter IEnvironmental Protection Agency1 – 1099
Subchapter CAir Programs50 – 99
Part 50National Primary and Secondary Ambient Air Quality Standards50.1 – 50.20
Part 51Requirements for Preparation, Adoption, and Submittal of Implementation Plans51.1 – 51.1319
Part 52Approval and Promulgation of Implementation Plans52.01 – 52.2999
Part 53Ambient Air Monitoring Reference and Equivalent Methods53.1 – 53.66
Part 54Prior Notice of Citizen Suits54.1 – 54.3
Part 55Outer Continental Shelf Air Regulations55.1 – 55.15
Part 56Regional Consistency56.1 – 56.7
Part 57Primary Nonferrous Smelter Orders57.101 – 57.816
Part 58Ambient Air Quality Surveillance58.1 – 58.61
Part 59National Volatile Organic Compound Emission Standards for Consumer and Commercial Products59.1 – 59.699
Part 60Standards of Performance for New Stationary Sources60.1 – 60.5805a
Part 61National Emission Standards for Hazardous Air Pollutants61.01 – 61.359
Part 62Approval and Promulgation of State Plans for Designated Facilities and Pollutants62.01 – 62.16730
Part 63National Emission Standards for Hazardous Air Pollutants for Source Categories63.1 – 63.12099
Part 64Compliance Assurance Monitoring64.1 – 64.10
Part 65Consolidated Federal Air Rule65.1 – 65.169
Part 66Assessment and Collection of Noncompliance Penalties by EPA66.1 – 66.95
Part 67EPA Approval of State Noncompliance Penalty Program67.1 – 67.43
Part 68Chemical Accident Prevention Provisions68.1 – 68.220
Part 69Special Exemptions from Requirements of the Clean Air Act69.11 – 69.52
Part 70State Operating Permit Programs70.1 – 70.14
Part 71Federal Operating Permit Programs71.1 – 71.27
Part 72Permits Regulation72.1 – 72.96
Part 73Sulfur Dioxide Allowance System73.1 – 73.90
Part 74Sulfur Dioxide Opt-Ins74.1 – 74.61
Part 75Continuous Emission Monitoring75.1 – 75.75
Part 76Acid Rain Nitrogen Oxides Emission Reduction Program76.1 – 76.15
Part 77Excess Emissions77.1 – 77.6
Part 78Appeal Procedures78.1 – 78.20
Part 79Registration of Fuels and Fuel Additives79.1 – 79.68
Part 80Regulation of Fuels and Fuel Additives80.1 – 80.1479
Part 81Designation of Areas for Air Quality Planning Purposes81.1 – 81.457
Part 82Protection of Stratospheric Ozone82.1 – 82.306
Part 83 [Reserved]
Part 84Phasedown of Hydrofluorocarbons84.1 – 84.64
Part 85Control of Air Pollution from Mobile Sources85.501 – 85.2401
Part 86Control of Emissions from New and In-Use Highway Vehicles and Engines86.1 – 86.1999
Part 87Control of Air Pollution from Aircraft and Aircraft Engines87.1 – 87.60
Part 88Clean-Fuel Vehicles88.1 – § 88.2 through 88.3
Part 89Control of Emissions from New and In-Use Nonroad Compression-Ignition Engines89.1 – § 89.2 through 89.3
Part 90Control of Emissions from Nonroad Spark-Ignition Engines at or Below 19 Kilowatts90.1 – § 90.2 through 90.3
Part 91Control of Emissions from Marine Spark-Ignition Engines91.1 – § 91.2 through 91.3
Part 92Control of Air Pollution from Locomotives and Locomotive Engines92.1 – § 92.2 through 92.3
Part 93Determining Conformity of Federal Actions to State or Federal Implementation Plans93.100 – 93.165
Part 94Control of Emissions from Marine Compression-Ignition Engines94.1 – § 94.2 through 94.3
Part 95Mandatory Patent Licenses95.1 – 95.4
Part 96NOX Budget Trading Program and CAIR NOX and SO2 Trading Programs for State Implementation Plans96.1 – 96.388
Part 97Federal NOX Budget Trading Program, CAIR NOX and SO2 Trading Programs, CSAPR NOX and SO2 Trading Programs, and Texas SO2 Trading Program97.1 – 97.1035
Part 98Mandatory Greenhouse Gas Reporting98.1 – 98.478
Part 99 [Reserved]