§ 322-c. Gas space heating appliances to be equipped with back draft diverters and automatic shutoff devices. On and after July first, nineteen hundred sixty-five it shall be unlawful to manufacture or assemble, or to sell or offer for sale, or to install, use or maintain in any building used or occupied as a residence, any space heating appliance using natural and/or manufactured gas fuel unless such appliance is equipped with (a) a back draft diverter with vents of sufficient capacity to permit the discharge of combustion gases away from the burning gas, except where such appliance (i) is provided with a sealed combustion chamber directly vented to the outside, or (ii) is listed by an accredited third party agency as an unvented appliance in compliance with American National Standard Z21.11.2 and meets or exceeds standards established by rules and regulations promulgated, and which may be periodically amended, by the department of health and approved by the state fire prevention and building code council, and (b) an automatic shutoff device to prevent the flow of gas if the flame or pilot light, thereof is extinguished; provided, however, that nothing contained herein shall be construed as repealing or in any manner limiting, restricting or diminishing any power conferred by any provision of law upon any city having a population of one million or more, or any body, agency or officer thereof, to enact or adopt local laws, ordinances, other local enactments or rules or regulations relating in any manner to gas space heating appliances, so long as such local laws, ordinances, enactments, rules or regulations in so far as the same relate to the subject matter of this section, are not less restrictive than the provisions of this section. A violation of the provisions of this section shall constitute a misdemeanor.