“Fire alarm system” means any mechanical or electrical device which is designed to detect or used for detection of smoke and/or heat within a building, structure, facility, watercraft, or any portion thereof which, when activated, emits a sound, displays a light, or transmits a signal or message for the purpose of alerting occupants or others to the existence of a fire emergency. “Fire alarms systems” include but are not limited to direct-dial telephone devices, audible alarms, and proprietor alarms. Devices which are not designed or used to register alarms that are audible, visible, or perceptible outside of the protected building, structure, facility, or watercraft are not included within this definition, nor are auxiliary devices installed for the telephone company systems which might be damaged or disrupted by the use of alarm system. (Ord. 79-2 § 2, 1979.)