| Air quality control region |
Pollutant |
| Particulate matter |
Sulfur oxides |
Nitrogen dioxide |
Carbon monoxide |
Ozone |
| Greater Metropolitan Cleveland Intrastate |
I |
I |
III |
III |
I |
| Huntington (West Virginia)-Ashland (Kentucky)-Portsmouth-Ironton (Ohio) Interstate |
I |
III |
III |
III |
III |
| Mansfield-Marion Intrastate |
II |
II |
III |
III |
III |
| Metropolitan Cincinnati Interstate |
I |
II |
III |
III |
I |
| Metropolitan Columbus Intrastate |
I |
III |
III |
III |
I |
| Metropolitan Dayton Intrastate |
I |
II |
III |
III |
I |
| Metropolitan Toledo Interstate |
I |
I |
III |
III |
I |
| Northwest Ohio Intrastate |
II |
I |
III |
III |
III |
| Northwest Pennsylvania-Youngstown Interstate |
I |
II |
III |
III |
III |
| Parkersburg (West Virginia)-Marietta (Ohio) Interstate |
I |
II |
III |
III |
III |
| Sandusky Intrastate |
III |
III |
III |
III |
III |
| Steubenville-Weirton-Wheeling Interstate |
I |
I |
III |
III |
III |
| Wilmington-Chillicothe-Logan Intrastate |
III |
III |
III |
III |
III |
| Zanesville-Cambridge Intrastate |
II |
IA |
III |
III |
III |