It shall be unlawful for any person to smoke or possess any lighted substance aboard any transit bus in revenue service within the City.

Transit bus shall mean any vehicle designed to carry 15 or more passengers, transporting the general public in urban, suburban or interurban service. Excluded are intercity passenger stage corporations regulated by the Public Utilities Commission, and charter operations which are not available to the general public.

Revenue service shall mean that period of time when the vehicle is in operation for the purpose of transportation of passengers and that period of time when parked at terminal points prior to departure.