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8-Hour Ozone (2008) Nonattainment Area Summary

Data is current as of March 31, 2024


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