PM-2.5 (1997) Maintenance Area (Redesignated from Nonattainment) SummaryAs of September 22, 2016
|Classification||Number of Areas||Number of Counties||2010 Population|
|Former Subpart 1||20||103||46,455,248|
County subtotals and grand totals may not equal sum of parts. Part counties are only counted one time within groupings. Multi-state nonattainment areas are not considered maintenance areas until all states in the area have been redesignated
The 1997 PM-2.5 Philadelphia-Wilmington, PA-NJ-DE nonattainment area, county and population are included in the Moderate classification grouping. NJ was classified as Subpart 1 at redesignation (effective September 4, 2013, 78 FR 54396), while PA and DE were classified as Moderate at redesignation. DE was redesignated effective September 4, 2014 79 FR 45350, and PA was redesignated effective April 21, 2015 80 FR 22112 .