Regulations last checked for updates: May 19, 2024

Title 40 - Protection of Environment last revised: May 16, 2024
§ 52.221 - Classification of regions.

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

Table 1 to § 52.221

Air quality control region Pollutant
Particulate matter Sulfur oxides Nitrogen dioxide Carbon monoxide Photochemical oxidants (hydrocarbons)
Great Basin Valley IntrastateIIIIIIIIIIIII
Lake County IntrastateIIIIIIIIIIII
Lake Tahoe IntrastateIIIIIIIIIIII
Metropolitan Los Angeles IntrastateIIIIIIIII
Mountain Counties IntrastateIIIIIIIIII
North Central Coast IntrastateIIIIIIIIIIII
North Coast IntrastateIIIIIIIIIIIIII
Northeast Plateau IntrastateIIIIIIIIIIIIIII
Sacramento Valley IntrastateIIIIIIIIII
San Diego IntrastateIIIIIIIIII
San Francisco Bay Area IntrastateIIIIIIIIII
San Joaquin Valley IntrastateIIIIIIIIII
South Central Coast IntrastateIIIIIIIIIIIII
Southeast Desert IntrastateIIIIIIIIIII
[86 FR 16537, Mar. 30, 2021]

authority: 42 U.S.C. 7401
cite as: 40 CFR 52.221