The Nebraska plan was evaluated on the basis of the following classifications:
| Air quality control region
| Pollutant
|
|---|
| Particulate matter
| Sulfur oxides
| Nitrogen dioxide
| Carbon monoxide
| Photochemical oxidants (hydrocarbons)
|
|---|
| Metropolitan Omaha-Council Bluffs Interstate | I | II | III | III | III
|
| Lincoln-Beatrice-Fairbury Intrastate | II | III | III | III | III
|
| Metropolitan Sioux City Interstate | III | III | III | III | III
|
| Nebraska Intrastate | III | III | III | III | III |