Regulations last checked for updates: Nov 24, 2024

Title 40 - Protection of Environment last revised: Nov 21, 2024
§ 52.1171 - Classification of regions.

The Michigan plan was evaluated on the basis of the following classifications:

Air quality control region Pollutant
Particulate matter Sulfur oxides Nitrogen dioxide Carbon monoxide Ozone
Metropolitan Detroit-Port Huron IntrastateIIIIIIIIIII
Metropolitan Toledo InterstateIIIIIIIII
South Central Michigan IntrastateIIIIIIIIIIIII
South Bend-Elkhart (Indiana)-Benton Harbor (Michigan) InterstateIIAIIIIIIIII
Central Michigan IntrastateIIIIIIIIIIIIII
Upper Michigan IntrastateIIIIIIIIIIIIIII
[37 FR 10873, May 31, 1972, as amended at 39 FR 16346, May 8, 1974; 45 FR 29801, May 6, 1980]
authority: 42 U.S.C. 7401
cite as: 40 CFR 52.1171