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EPA Takes Three Major Actions to Address Air Quality

California Waiver Authority on GHG Tailpipe Emissions - EPA took final action to restore the state of California’s waiver authority to establish greenhouse gas vehicle tailpipe emissions standards for cars and light trucks. The waiver was revoked during the Trump Administration. The Biden Administration has a taken final action to allow California to set standards and for other states to adopt the California standard.


Truck and Heavy-Duty Vehicle NOx Rule - EPA issued a proposed rule to reduce nitrogen oxide emissions from trucks and heavy-duty vehicles and update greenhouse gas emission standards for some categories of commercial vehicles for model year 2027 and beyond.

Regional Ozone Transport - EPA issued a proposed federal implementation plan to address ozone cross state air pollution – or ozone precursors generated in one state that transport to neighboring states and reduce the air quality. The proposed federal implementation plan found that ozone precursors generated in 26 “upwind” states (Alabama, Arkansas, California, Delaware, Illinois, Indiana, Kentucky, Louisiana, Maryland, Michigan, Minnesota, Mississippi, Missouri, Nevada, New Jersey, New York, Ohio, Oklahoma, Pennsylvania, Tennessee, Texas, Utah, Virginia, West Virginia, Wisconsin, and Wyoming) prevented neighboring “downwind” states from meeting the 2015 ozone standard. The proposed federal implementation plan establishes actions that upwind states must take to reduce the transport of ozone precursors to neighboring states.

Last Reviewed: March 2022