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Ground-level Ozone Pollution

Rules that Help States Reduce Emissions and Meet Ozone Standards

State and Local Transportation Resources: Learn how Transportation Conformity, travel efficiency strategies, and other tools help states to achieve air quality and transportation objectives. 

General Conformity Rule: This rule ensures that action taken by federal agencies in nonattainment and maintenance areas do not interfere with a state’s plan to meet national air standards. 

Documents concerning the review and handling of Exceptional Events: Exceptional events are unusual or naturally occurring events that can affect air quality but are not reasonably controllable using techniques that tribal, state or local agencies may implement in order to attain and maintain the national air standards.