8-Hour Ozone (2008) Nonattainment Area Summary

Data is current as of September 30, 2024

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Classification	Number of Areas	Number of Counties	2010 Population
Extreme	3	12	19,987,656
Severe 15	9	58	42,020,413
Serious	3	7	2,534,484
Moderate	5	10	6,707,941
Marginal	14	46	19,037,118
SUBTOTAL	34	133	90,287,612
GRAND TOTAL	34	133	90,287,612

County subtotals and grand totals may not equal sum of parts. Part counties are only counted one time across groupings. Multi-state nonattainment areas are not considered maintenance areas until all states in the area have been redesignated