U.S. Code of Federal Regulations

Regulations most recently checked for updates: Aug 27, 2025

All TitlesTitle 40Chapter IPart 52Subpart Q - Subpart Q—Iowa
View all text of Subpart Q [§ 52.820 - § 52.842]
§ 52.821 - Classification of regions.

The Iowa plan was evaluated on the basis of the following classification:

Air quality control region Pollutant
Particulate matter Sulfur oxides Nitrogen dioxide Carbon monoxide Photochemical oxidants (hydrocarbons)
Metropolitan Omaha-Council Bluffs InterstateIIIIIIIIIIII
Metropolitan Sioux Falls InterstateIIIIIIIIIIIIII
Metropolitan Sioux City InterstateIIIIIIIIIIIIIII
Metropolitan Dubuque InterstateIIIIIIIIIIIII
Metropolitan Quad Cities InterstateIIIIIIIIIIIII
Burlington-Keokuk InterstateIIIIIIIIIII
Northwest Iowa IntrastateIIIIIIIIIIIIIII
North Central Iowa IntrastateIAIIIIIIIIIIII
Northeast Iowa IntrastateIIIIIIIIIIIII
Southwest Iowa IntrastateIIIIIIIIIIIIIII
South Central Iowa IntrastateIIIIIIIIIII
Southeast Iowa IntrastateIIIIIIIIIIIIIII
[37 FR 10865, May 31, 1972, as amended at 39 FR 16346, May 8, 1974]
© 2016 GovRegs | About | Disclaimer | Privacy