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Title 40

Displaying title 40, up to date as of 7/20/2026. Title 40 was last amended 7/16/2026.
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  1. Title 40 —Protection of Environment
  2. Chapter I —Environmental Protection Agency
  3. Subchapter C —Air Programs
  4. Part 51 —Requirements for Preparation, Adoption, and Submittal of Implementation Plans
  5. Subpart AA   View Full Text
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Title 40Protection of EnvironmentPart / Section
Chapter IEnvironmental Protection Agency1 – 1099
Subchapter CAir Programs50 – 99
Part 51Requirements for Preparation, Adoption, and Submittal of Implementation Plans51.1 – 51.1403
Subpart AAProvisions for Implementation of the 2008 Ozone National Ambient Air Quality Standards51.1100 – 51.1119
§ 51.1100Definitions.
§ 51.1101Applicability of part 51.
§ 51.1102Classification and nonattainment area planning provisions.
§ 51.1103Application of classification and attainment date provisions in CAA section 181 to areas subject to § 51.1102.
§ 51.1104 [Reserved]
§ 51.1105Transition from the 1997 ozone NAAQS to the 2008 ozone NAAQS and anti-backsliding.
§ 51.1106Redesignation to nonattainment following initial designations.
§ 51.1107Determining eligibility for 1-year attainment date extensions for the 2008 ozone NAAQS under CAA section 181(a)(5).
§ 51.1108Modeling and attainment demonstration requirements.
§ 51.1109 [Reserved]
§ 51.1110Requirements for reasonable further progress (RFP).
§ 51.1111 [Reserved]
§ 51.1112Requirements for reasonably available control technology (RACT) and reasonably available control measures (RACM).
§ 51.1113Section 182(f) NOX exemption provisions.
§ 51.1114New source review requirements.
§ 51.1115Emissions inventory requirements.
§ 51.1116Requirements for an Ozone Transport Region.
§ 51.1117Fee programs for Severe and Extreme nonattainment areas that fail to attain.
§ 51.1118Suspension of SIP planning requirements in nonattainment areas that have air quality data that meet an ozone NAAQS.
§ 51.1119Applicability.
eCFR Content