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  2. Regulations for Emissions from Vehicles and Engines

Proposed Rule and Related Materials for Control of Emissions of Air Pollution From Nonroad Diesel Engines Control of Air Pollution From Aircraft and Aircraft Engines; Proposed Emission Standards and Test Procedures

Related Topic
  • Final Rule for Control of Air Pollution From Aircraft and Aircraft Engines; Emission Standards and Test Procedures

EPA is proposing to adopt emission standards and related provisions for aircraft gas turbine engines with rated thrusts greater than 26.7 kilonewtons. These engines are used primarily on commercial passenger and freight aircraft. The proposed requirements were either previously adopted by the International Civil Aviation Organization (ICAO), or agreed on at ICAO’s Committee on Aviation Environmental Protection (CAEP) in 2010. Included in the proposal are two new tiers of more stringent emission standards for oxides of nitrogen (NOx). These are referred to as Tier 6 (or CAEP/6) standards and Tier 8 (or CAEP/8) standards. The proposed standards would become effective for newly-manufactured aircraft engines beginning in 2013.

  • Proposed Rule: Control of Air Pollution From Aircraft and Aircraft Engines; Proposed Emission Standards and Test Procedures (pdf) (530 KB, published Jul 27, 2011)

Regulations for Emissions from Vehicles and Engines

  • Onroad
    • Passenger Vehicles
    • Commercial Trucks & Buses
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  • Nonroad
    • Aircraft
    • Heavy Equipment
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  • Greenhouse Gas
Contact Us About Regulations for Emissions from Vehicles and Engines
Contact Us About Regulations for Emissions from Vehicles and Engines to ask a question, provide feedback, or report a problem.
Last updated on April 22, 2025
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