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8-Hour Ozone (2008) Nonattainment Area Summary

Data is current as of January 31, 2023


Classification Number of Areas Number of Counties 2010 Population
Extreme 2 12 19,561,850
Severe 15 10 58 42,446,219
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