No passenger while traveling upon, and no employee while engaged in the operation of, a common carrier motor bus, passenger railroad car or school bus, as defined in section 14-275, shall have a lighted cigarette, cigar or pipe in his possession. This section shall not apply to any special bus or to any compartment or part of a regular bus or passenger railroad car especially provided or set apart for smoking therein. Violation of any provision of this section shall be an infraction.