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Title 40

Displaying title 40, up to date as of 6/09/2026. Title 40 was last amended 6/08/2026.
There have been changes in the last two weeks to Part 52.
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Title 40Protection of EnvironmentPart / Section
Chapter IEnvironmental Protection Agency1 – 1099
Subchapter CAir Programs50 – 99
Part 52Approval and Promulgation of Implementation Plans52.01 – 52.2999
Subpart AGeneral Provisions52.01 – 52.46
Subpart BAlabama52.49 – 52.69
Subpart CAlaska52.70 – 52.98
Subpart DArizona52.119 – 52.153
Subpart EArkansas52.170 – 52.200
Subpart FCalifornia52.220 – 52.285
Subpart GColorado52.319 – 52.354
Subpart HConnecticut52.369 – 52.388
Subpart IDelaware52.420 – 52.465
Subpart JDistrict of Columbia52.470 – 52.515
Subpart KFlorida52.519 – 52.540
Subpart LGeorgia52.569 – 52.590
Subpart MHawaii52.620 – 52.634
Subpart NIdaho52.670 – 52.691
Subpart OIllinois52.719 – 52.750
Subpart PIndiana52.769 – 52.800
Subpart QIowa52.820 – 52.842
Subpart RKansas52.869 – 52.884
Subpart SKentucky52.919 – 52.941
Subpart TLouisiana52.970 – 52.1018
Subpart UMaine52.1019 – 52.1037
Subpart VMaryland52.1070 – 52.1118
Subpart WMassachusetts52.1119 – 52.1169
Subpart XMichigan52.1170 – 52.1190
Subpart YMinnesota52.1219 – 52.1241
Subpart ZMississippi52.1270 – 52.1284
Subpart AAMissouri52.1319 – 52.1343
Subpart BBMontana52.1370 – 52.1398
Subpart CCNebraska52.1420 – 52.1437
Subpart DDNevada52.1470 – 52.1492
Subpart EENew Hampshire52.1519 – 52.1535
Subpart FFNew Jersey52.1570 – 52.1607
Subpart GGNew Mexico52.1620 – 52.1640
Subpart HHNew York52.1670 – 52.1690
Subpart IINorth Carolina52.1769 – 52.1785
Subpart JJNorth Dakota52.1820 – 52.1837
Subpart KKOhio52.1870 – 52.1894
Subpart LLOklahoma52.1919 – 52.1960
Subpart MMOregon52.1970 – 52.2019
Subpart NNPennsylvania52.2020 – 52.2065
Subpart OORhode Island52.2070 – 52.2089
Subpart PPSouth Carolina52.2120 – 52.2141
Subpart QQSouth Dakota52.2170 – 52.2186
Subpart RRTennessee52.2219 – 52.2241
Subpart SSTexas52.2270 – 52.2312
Subpart TTUtah52.2320 – 52.2356
Subpart UUVermont52.2370 – 52.2386
Subpart VVVirginia52.2420 – 52.2465
Subpart WWWashington52.2470 – 52.2502
Subpart XXWest Virginia52.2520 – 52.2565
Subpart YYWisconsin52.2569 – 52.2594
Subpart ZZWyoming52.2620 – 52.2637
Subpart AAAGuam52.2670 – 52.2686
Subpart BBBPuerto Rico52.2720 – 52.2732
Subpart CCCVirgin Islands52.2770 – 52.2782
Subpart DDDAmerican Samoa52.2820 – 52.2827
Subpart EEEApproval and Promulgation of Plans52.2850
Subpart FFFCommonwealth of the Northern Mariana Islands52.2900 – 52.2999
Appendixes A-C to Part 52 [Reserved]
Appendix D to Part 52
Determination of Sulfur Dioxide Emissions From Stationary Sources by Continuous Monitors
Appendix E to Part 52
Performance Specifications and, Specification Test Procedures for Monitoring Systems for Effluent Stream Gas Volumetric Flow Rate
Appendix F to Part 52
Clean Air Act Section 126 Petitions From Eight Northeastern States: Named Source Categories and Geographic Coverage