In a final rule, the U.S. Environmental Protection Agency (EPA) is replacing the existing smoke standard on civil subsonic jet airplanes with rated engine outputs exceeding 26.7 kilonewtons (6,002 pounds of thrust) with particle matter (PM) standards. These standards apply to in-production engines manufactured on or after Jan. 1, 2023, as well as type designs with initial type certification applications submitted on or after that same date.
The EPA is maintaining smoke number standards for new-production engines not covered by the PM mass concentration standard and for engines already manufactured. The PM standards and test procedures are equivalent to the engine standards adopted by the United Nations’ International Civil Aviation Organization (ICAO) in 2017 and 2020.
According to the final rule, the EPA and FAA actively participated in the proceedings in which the ICAO requirements were developed. “These standards reflect the importance of the control of PM emissions and U.S. efforts to secure the highest practicable degree of uniformity in aviation regulations and standards. As part of this update, the EPA is also aligning with ICAO by applying the smoke number standards to engines with less than or equal to 26.7 kilonewtons of rated output used on supersonic airplanes.