Conn. Gen. Stat. § 14-80a: Maximum noise levels. Regulations.

(a) No person shall operate a vehicle or combination of vehicles, nor shall the owner of any vehicle allow the vehicle to be operated, at any time or under any condition of grade, surface, speed, load, acceleration, deceleration or weather condition in such a manner as to exceed the decibel levels established under subsection (c) of this section. This subsection applies to the total noise generated by a vehicle and shall not be construed as limiting or precluding the enforcement of any other motor vehicle noise provisions of this title.

(b) No person shall sell or offer for sale a new vehicle which produces a maximum decibel level which exceeds the decibel levels established under subsection (c) of this section.

(c) The Commissioner of Motor Vehicles shall, with the advice of the Commissioner of Energy and Environmental Protection, adopt regulations, in accordance with the provisions of chapter 54, establishing (1) the maximum decibel levels permissible for motor vehicles, which shall not exceed the maximum decibel levels established for motor vehicles by federal law or regulation, and (2) the procedure for testing maximum decibel levels. The commissioner shall amend such regulations to reflect industry standards and advancements in technology and shall submit the amended regulations to the standing legislative regulation review committee under section 4-170 not later than October 1, 2024.

(d) Violation of the provisions of this section shall be an infraction.