Which device is associated with a supervisory signal in a dry-type system?

Which device is associated with a supervisory signal in a dry-type system?

• A. Manual pull station
• B. Smoke detector
• C. Air pressure switch in a dry-type system
• D. Heat detector

Answer: (C)

In a dry-pipe (dry-type) sprinkler system, keeping the main dry-pipe valve charged is essential. The air pressure switch monitors the air pressure in that system. If the pressure drops or becomes abnormal—indicating the system may not be properly charged or a valve action has occurred—the switch sends a supervisory signal to the fire alarm panel. This type of signal alerts facility personnel to a condition that could affect system readiness, without indicating an active fire. Manual pull stations, smoke detectors, and heat detectors are designed to trigger alarm signals when a fire or manual actuation occurs, not to indicate a maintenance or readiness issue.

In a dry-pipe (dry-type) sprinkler system, keeping the main dry-pipe valve charged is essential. The air pressure switch monitors the air pressure in that system. If the pressure drops or becomes abnormal—indicating the system may not be properly charged or a valve action has occurred—the switch sends a supervisory signal to the fire alarm panel. This type of signal alerts facility personnel to a condition that could affect system readiness, without indicating an active fire. Manual pull stations, smoke detectors, and heat detectors are designed to trigger alarm signals when a fire or manual actuation occurs, not to indicate a maintenance or readiness issue.