Who regulates airplane noise?

The Federal Aviation Administration (FAA), under Federal Aviation Regulation Part 36, governs the certification of aircraft as it relates to noise levels. Depending on the type of aircraft, FAR Part 36 determines the maximum allowable noise level. The FAA also follows the model of the International Civil Aviation Organization (ICAO) which sets global aircraft noise standards known as Stages. Currently, the FAA mandates that nearly all aircraft that fly within the United States comply with Stage 3 requirements.