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Title 40

Displaying title 40, up to date as of 9/21/2021. Title 40 was last amended 9/21/2021.
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Title 40 Protection of Environment Part / Section
Chapter I Environmental Protection Agency 1 – 1099
Subchapter C Air Programs 50 – 99
Part 81 Designation of Areas for Air Quality Planning Purposes 81.1 – 81.437
Subpart A Meaning of Terms 81.1
§ 81.1 Definitions.
Subpart B Designation of Air Quality Control Regions 81.11 – 81.276
Subpart C Section 107 Attainment Status Designations 81.300 – 81.356
Subpart D Identification of Mandatory Class I Federal Areas Where Visibility Is an Important Value 81.400 – 81.437
Appendix A to Part 81
Air Quality Control Regions (AQCR's)