Conn. Gen. Stat. § 14-100b
On and after January 1, 1968, no passenger motor vehicle designated as a 1968 or later model shall be registered in this state unless equipped with an effective air pollution control device. The Commissioner of Energy and Environmental Protection, with the advice of the Commissioner of Motor Vehicles, may make regulations establishing standards for such devices, which standards shall be consistent with provisions of federal law, if any, relating to control of emissions from the vehicles concerned. The Commissioner of Motor Vehicles shall not require, as a condition precedent to the initial sale of a vehicle or vehicular equipment, the inspection, certification or other approval of any feature or equipment designed for the control of emissions from motor vehicles if such feature or equipment has been certified, approved or otherwise authorized pursuant to federal law.
Conn. Gen. Stat. § 14-100b
(1967, P.A. 676; 1971, P.A. 872, S. 29; P.A. 11-80, S. 1.)