Air Pollutants - Particulate Matter (PM) - Standards & Requirements
Nonattainment Boundaries and Designations
The Clean Air Act requires the U.S. Environmental Protection Agency (EPA) to identify areas in each state using these three designations:
- Attainment - area meets a National Ambient Air Quality Standard (standard)
- Nonattainment - area does not meet (or is contributing to nearby areas in not meeting) a standard
- Unclassifiable - there is not enough data to designate the area under a new or revised standard
EPA sets boundaries for areas designated nonattainment and unclassifiable based on recommendations from the states. States use ambient air monitoring networks, emissions inventories, EPA guidance, and other relevant information to make these recommendations. Furthermore, states and EPA request public input during the process.
For more information please contact the Bureau of Air Quality at (803) 898-4123 or by email.