Although certain states impose their own standards, federal regulations pertaining to motorcycle exhaust systems are handled by the Environmental Protection Agency (EPA). The EPA has imposed noise emission regulations on exhaust systems produced on or after particular model years. In addition, labelling requirements are imposed to ensure that exhaust systems are in compliance with these standards. These regulations are covered by Section 6 of the Noise Control Act.
For on-street motorcycles, exhaust systems produced in or after model year 1983 may not exceed noise levels of 83 decibels (dB), and models produced in or after model year 1986 may not exceed noise levels of 80 dB. Mopeds produced in or after 1983 may not exceed noise levels of 80 dB, and off-road motorcycles with engine displacements greater than 80 cubic centimetres may not exceed noise levels of 82 dB.
EPA requirements stipulate that manufacturers must label exhaust systems to demonstrate compliance with noise standards. These labels must declare that the exhaust system "meets EPA noise emission requirements" unless the exhaust system is exempt from standard rules. For instance, if it was built prior to 1983.
The EPA stipulates that its administrator may require certain manufacturers to conduct testing to demonstrate compliance regulations. Failure to comply, either by producing exhaust systems that are too loud or by failing to label or properly test exhaust systems, may result in an order to cease manufacturing.