52.71—Classification of regions.
The Alaska plan was evaluated on the basis of the following classifications:
| Air quality control Region | Pollutant | ||||
|---|---|---|---|---|---|
| Particulate matter | Sulfur oxides | Nitrogen dioxide | Carbon monoxide | Ozone | |
| Cook Inlet Intrastate | I | III | III | I | III. |
| Northern Alaska Intrastate | I | III | III | I | III. |
| South Central Alaska Intrastate | III | III | III | III | III. |
| Southeastern Alaska Intrastate | III | III | III | III | III. |