Conformity

Updated: September 3, 2024

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Conformity refers to the Clean Air Act requirements for federal actions to comply with the National Ambient Air Quality Standards. The general Conformity rule ensures that every action that a federal agency undertakes, approves, permits or supports will conform to the appropriate State Implementation Plan (SIP). Transportation conformity is required to ensure federal funding and approval are given to highway and transit projects consistent with the air quality goals established by the SIP.