When can an ACO say that an alarm system is UL approved or listed?

• A. Only if the entire system is UL approved or listed
• B. If only some components are UL listed, the system can be advertised as UL approved
• C. The entire system and all components must be UL approved or listed
• D. UL approval status is not related to the system as a whole

Answer: (C)

UL listing is a safety certification that applies to a product or to a fully tested system. For an alarm system, you can state that the system is UL approved or UL listed only when every part of the system—control panel, sensors, detectors, power supply, wiring, and the installation configuration—has UL listing or approval. If any component isn’t UL listed, claiming the entire system as UL approved would be misleading. In that case you can reference UL-listed components individually, but not the system as a whole. The main idea is that UL status is meaningful only when the complete system, with all components, has been evaluated and certified as a whole.