As of May 31,
2025, the EPA announced that the number of nonattainment areas
are 46 ozone (8-hour 2015 standard), 34 ozone (8-hour 2008 standard),
5 PM-2.5 (2012 standard), 11 PM-2.5 (2006 standard), 21 PM10
(1987), 28 sulfur dioxide (2010 standard), 7 sulfur dioxide (1971
standard), 1 lead (1978 standard), and 11 lead (2008 standard)
in the United States. There are no CO and NO2 nonattainment areas
in the United States. Maps of the nonattainment areas are available
for review and download.
