For an elevator with a sprinklered machine room and a non-sprinklered hoistway, how many fire alarm control outputs are required?

• A. 2
• B. 3
• C. 4
• D. 5

Answer: (C)

The main idea is that elevator fire alarm interfacing requires a separate control output for each area that can be affected in a fire, with independent signals for different functions. When one part of the elevator system (the machine room) is sprinklered and another part (the hoistway) is not, those signals must be kept separate to ensure reliable fire service operation and proper coordination of safety actions.

In this mixed setup you need one output to initiate fire service/recall for the machine room, plus another output to supervise or signal the sprinkler system protecting that room. You also need separate outputs for the hoistway to handle its fire service action and its own shaft-related safety coordination. These four distinct control paths ensure that the machine room and hoistway can operate safely and independently during a fire, which is why four fire alarm control outputs are required.