| Applies to... | Acronym | Full name |
| Major new/modified stationary sources of criteria air pollutants in attainment areas | |
| New/modified stationary sources of criteria air pollutants | |
| Existing dischargers (1989-present) | |
| Existing stationary sources of criteria air pollutants in non-attainment areas | |
| Major stationary sources of hazardous air pollutants | |
| Major new/modified stationary sources of criteria air pollutants in non-attainment areas | |
| Area stationary sources of hazardous air pollutants | |
| Existing dischargers (1977-89) | |
| New dischargers | |