Final rule · 2026-07399

Air Plan Approval; Pennsylvania; Redesignation Request for the Allegheny County Area for the 2012 Annual Fine Particulate Matter Standard

The Environmental Protection Agency (EPA) is approving the Commonwealth of Pennsylvania's request to redesignate the Allegheny County, Pennsylvania nonattainment area (Allegheny County Area) to attainment for the 2012 annual fine particulate matter (PM<INF>2.5</INF>) national ambient air quality standards (NAAQS or standard). The redesignation request was submitted by the Commonwealth of Pennsylvania Department of Environmental Protection (PADEP or Pennsylvania) on behalf of the Allegheny County Health Department (ACHD). This action is being taken under the CAA.