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Regulations for Emissions from Vehicles and Engines

Final Rule for Finding That Greenhouse Gas Emissions From Aircraft Cause or Contribute to Air Pollution That May Reasonably Be Anticipated To Endanger Public Health and Welfare

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Rule Summary

The EPA finalized findings that greenhouse gas (GHG) emissions from certain classes of engines used in aircraft contribute to the air pollution that causes climate change endangering public health and welfare under section 231(a) of the Clean Air Act. These findings focus on the six well-mixed GHGs that together represent the largest driver of human-caused climate change: carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride. The EPA’s final endangerment and contribution findings for aircraft GHG emissions are in preparation for a future domestic rulemaking process to adopt future GHG standards. Any future proposed aircraft engine standards would also be open to public comment and review before they could take effect. 

Rule History

Proposed Rule and Related Materials

The EPA proposed to find that greenhouse gas (GHG) emissions from certain classes of engines used in aircraft contribute to the air pollution that causes climate change endangering public health and welfare under section 231(a) of the Clean Air Act. At the same time, EPA issued an Advance Notice of Proposed Rulemaking that provides information on the process for setting international carbon dioxide (CO2) emissions standards for aircraft at the International Civil Aviation Organization, and describes and seeks input on issues related to setting an international CO2 standard for aircraft, and the potential use of section 231 of the Clean Air Act to adopt a corresponding aircraft engine standard domestically.

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