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Title 40

Displaying title 40, up to date as of 7/16/2026. Title 40 was last amended 7/16/2026.
There have been changes in the last two weeks to Subpart C.
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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 CSection 107 Attainment Status Designations81.300 – 81.356
§ 81.300Scope.
§ 81.301Alabama.
§ 81.302Alaska.
§ 81.303Arizona.
§ 81.304Arkansas.
§ 81.305California.
§ 81.306Colorado.
§ 81.307Connecticut.
§ 81.308Delaware.
§ 81.309District of Columbia.
§ 81.310Florida.
§ 81.311Georgia.
§ 81.312Hawaii.
§ 81.313Idaho.
§ 81.314Illinois.
§ 81.315Indiana.
§ 81.316Iowa.
§ 81.317Kansas.
§ 81.318Kentucky.
§ 81.319Louisiana.
§ 81.320Maine.
§ 81.321Maryland.
§ 81.322Massachusetts.
§ 81.323Michigan.
§ 81.324Minnesota.
§ 81.325Mississippi.
§ 81.326Missouri.
§ 81.327Montana.
§ 81.328Nebraska.
§ 81.329Nevada.
§ 81.330New Hampshire.
§ 81.331New Jersey.
§ 81.332New Mexico.
§ 81.333New York.
§ 81.334North Carolina.
§ 81.335North Dakota.
§ 81.336Ohio.
§ 81.337Oklahoma.
§ 81.338Oregon.
§ 81.339Pennsylvania.
§ 81.340Rhode Island.
§ 81.341South Carolina.
§ 81.342South Dakota.
§ 81.343Tennessee.
§ 81.344Texas.
§ 81.345Utah.
§ 81.346Vermont.
§ 81.347Virginia.
§ 81.348Washington.
§ 81.349West Virginia.
§ 81.350Wisconsin.
§ 81.351Wyoming.
§ 81.352American Samoa.
§ 81.353Guam.
§ 81.354Northern Mariana Islands.
§ 81.355Puerto Rico.
§ 81.356Virgin Islands.