Heat detectors in sprinklered elevator installations are required in which spaces?

• A. Elevator hoistway and machine room
• B. Elevator car and mechanical room
• C. Lobby and elevator hoistway
• D. Elevator car and lobby

Answer: (A)

In sprinklered elevator installations, heat detectors are placed in spaces whose conditions can directly affect elevator safety and operation: the hoistway and the machine room. The hoistway, or elevator shaft, is a confined vertical space where a fire can develop and spread into the shaft quickly; detecting heat there helps trigger appropriate fire response, such as recalling the car to a safe floor and ensuring the shaft is protected or isolated as needed. The machine room contains the hoist motor, controllers, and other equipment that could overheat or ignite; heat detectors in this space provide early warning to shut down or control equipment and raise alarms before a fire can compromise the elevator system or occupants.

Spaces like the elevator car and the lobby aren’t the ones specified for heat detectors in this scenario because the car is part of the shaft and typically relies on other safety strategies, and the lobby is generally covered by different detection approaches focused on widely occupied areas.