The Commercial Advertisement Loudness Mitigation (CALM) Act, was enacted on December 15, 2010 in response to consumer complaints about loud commercials. In the (CALM) Act, Congress directed the Federal Communications Commission to establish rules and make mandatory a technical standard for the volume of television commercials. Effective Dec. 13, 2012, these rules require commercials to have the same average volume as the programs they accompany. They apply to TV stations, cable operators or other multichannel video program distributors.
If you hear a commercial louder than the TV show it accompanies, you can file a complaint with the FCC by providing detailed information about the commercial.
Learn more at the FCC Encyclopedia.