The aircrafts conforms to ecological and environmental protection requirements of:Engine emission: Attachment #16 of the International Civil Aviation Convention, the secondvolume of "Emission of aircraft engines" July 1993, ICAO I and II parts, and chapters 1 and 2 of part III;Noise level: ICAO requirements in Chapter III of Attachment #16, where the normative sum ofthe noise level in the three points for the given type of aircrafts is set at 281EPNdB, however, the real sum is equal to 268,1 EPNdB (12,9 EPNdB favorable difference).Internal noise level in the passenger cabin: