Green Book
8-Hour Ozone (2008) Nonattainment Area Summary
As of September 22, 2016| Classification | Number of Areas | Number of Counties | 2010 Population |
| Extreme | 2 | 12 | 19,561,850 |
| Severe 15 | 3 | 9 | 3,535,243 |
| Serious | 2 | 2 | 824,175 |
| Moderate | 14 | 88 | 55,369,982 |
| Marginal | 22 | 107 | 40,110,200 |
| SUBTOTAL | 43 | 211 | 119,401,450 |
| GRAND TOTAL | 43 | 211 | 119,401,450 |
County subtotals and grand totals may not equal sum of parts. Part counties are only counted one time within groupings. Multi-state nonattainment areas are not considered maintenance areas until all states in the area have been redesignated