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Title 40

Displaying title 40, up to date as of 7/13/2026. Title 40 was last amended 7/13/2026.
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Title 40Protection of EnvironmentPart / Section
Chapter IEnvironmental Protection Agency1 – 1099
Subchapter CAir Programs50 – 99
Part 81Designation of Areas for Air Quality Planning Purposes81.1 – 81.457
Subpart DIdentification of Mandatory Class I Federal Areas Where Visibility Is an Important Value81.400 – 81.437
§ 81.400Scope.
§ 81.401Alabama.
§ 81.402Alaska.
§ 81.403Arizona.
§ 81.404Arkansas.
§ 81.405California.
§ 81.406Colorado.
§ 81.407Florida.
§ 81.408Georgia.
§ 81.409Hawaii.
§ 81.410Idaho.
§ 81.411Kentucky.
§ 81.412Louisiana.
§ 81.413Maine.
§ 81.414Michigan.
§ 81.415Minnesota.
§ 81.416Missouri.
§ 81.417Montana.
§ 81.418Nevada.
§ 81.419New Hampshire.
§ 81.420New Jersey.
§ 81.421New Mexico.
§ 81.422North Carolina.
§ 81.423North Dakota.
§ 81.424Oklahoma.
§ 81.425Oregon.
§ 81.426South Carolina.
§ 81.427South Dakota.
§ 81.428Tennessee.
§ 81.429Texas.
§ 81.430Utah.
§ 81.431Vermont.
§ 81.432Virgin Islands.
§ 81.433Virginia.
§ 81.434Washington.
§ 81.435West Virginia.
§ 81.436Wyoming.
§ 81.437New Brunswick, Canada.