If a smoke detector in an elevator lobby on the 4th floor activates, the fire alarm system ancillary contact should:

Question: If a smoke detector in an elevator lobby on the 4th floor activates, the fire alarm system ancillary contact should:

Answer options: ✅ Activate Phase I Elevator Recall

• Wait for manual confirmation by building staff
• Shut down all elevator power immediately without moving cabs
• Sound the alarm only inside the elevator cab

Correct answer: Activate Phase I Elevator Recall

Explanation: Elevator recall (Phase I) is triggered by smoke detectors in elevator lobbies, machine rooms, or hoistways. Heat detectors in these areas generally do not trigger recall but may trigger 'Shunt Trip' (power cut). S524 Appendix explains the logic.