Classification of regions.

Checkout our iOS App for a better way to browser and research.

§ 52.1921 Classification of regions.

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

Expand Table
Air quality control region Pollutant
Particulate matter Sulfur oxides Nitrogen dioxide Carbon monoxide Ozone
Central Oklahoma Intrastate I III III III I
Northeastern Oklahoma Intrastate I III III III I
Southeastern Oklahoma Intrastate III III III III III
North Central Oklahoma Intrastate III III III III III
Southwestern Oklahoma Intrastate III III III III III
Northwestern Oklahoma Intrastate III III III III III
Metropolitan Fort Smith Interstate II III III III III
Shreveport-Texarkana-Tyler Interstate II III III III III

[37 FR 10887, May 31, 1972, as amended at 45 FR 9741, Feb. 13, 1980]


Download our app to see the most-to-date content.