PM-2.5 (2006) Nonattainment Area Summary

Data is current as of November 30, 2025

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Classification	Number of Areas	Number of Counties	2010 Population
Serious	5	19	21,828,537
Moderate	5	16	9,430,471
SUBTOTAL	10	35	31,259,008
Former Subpart 1	0	0	0
SUBTOTAL	0	0	0
GRAND TOTAL	10	35	31,259,008

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