In a dry-pipe system, which component aids rapid air removal after sprinkler head actuation?

• A. Vent
• B. Exhauster
• C. Dampener
• D. Pressure relief valve

Answer: (B)

In a dry-pipe system, the piping is filled with pressurized air, and when a sprinkler head is actuated, that air must be expelled quickly so water can fill the pipes and reach the heads promptly. The exhauster is designed to actively pull air out of the dry-pipe system, accelerating the replacement of air with water and speeding up the delivery of water to the activated head. This makes it the most effective device for rapid air removal after actuation. A vent can release air at the highest points, but it doesn’t evacuate air as swiftly when a head has just opened. A dampener is used to smooth out pressure surges and water hammer, not to remove air, and a pressure relief valve protects against overpressure, not air removal.