Air Quality

Traffic congestionTransportation Conformity

Transportation conformity is a process required by the Clean Air Act Section 176(c) which establishes the framework for improving air quality to protect public health and the environment.  The goal of transportation conformity is to ensure that Federal Highway Administration (FHWA) and Federal Transit Administration (FTA) funding and approvals are given to highway and public transit activities that are consistent with air quality goals.  For additional information on transportation conformity visit:

The Clean Air Act requires that Long Range Transportation Plans (LRTPs), Transportation Improvement Programs (TIPs) and Federal projects conform to the purpose of the State Implementation Plan (SIP).  Conformity to a SIP means projects and programs will not cause or contribute to any new violations of the National Ambient Air Quality Standards (NAAQS); increase the frequency or severity of NAAQS violations; or delay timely attainment of the NAAQS or any required interim milestone. Conformity requirements apply in areas that either do not meet or previously have not met air quality standards for ozone, particulate matter, lead, sulfur dioxide, carbon monoxide or nitrogen dioxide. These areas are known as “nonattainment areas” or “maintenance areas,” respectively.  For more information on the transportation conformity process for LRTPs, TIPs and projects visit:

Attainment Status

Washington County, Maryland and Berkeley and Jefferson Counties in West Virginia are in attainment status for all critical pollutants.  For a complete list of nonattainment and maintenance areas visit: