Which sprinkler system type opens all heads in a zone to release water once activated?

Which sprinkler system type opens all heads in a zone to release water once activated?

• A. Deluge.
• B. Wet-pipe.
• C. Dry-pipe.
• D. Pre-action.

Answer: (A)

Deluge systems are designed so every sprinkler head in a zone is open to water. The pipes in the zone are filled (or kept pressurized) and there’s no valve to isolate individual heads. When the system is activated, water is released through all heads in that zone at once, providing immediate, total discharge. This is different from wet-pipe, where water-filled pipes release water only through the head that heats up; dry-pipe stores air in the piping and only fills with water after a valve trips; and pre-action requires a detection event before water enters the pipes. So the scenario described—opening all heads in a zone to release water upon activation—fits a deluge system.

Deluge systems are designed so every sprinkler head in a zone is open to water. The pipes in the zone are filled (or kept pressurized) and there’s no valve to isolate individual heads. When the system is activated, water is released through all heads in that zone at once, providing immediate, total discharge. This is different from wet-pipe, where water-filled pipes release water only through the head that heats up; dry-pipe stores air in the piping and only fills with water after a valve trips; and pre-action requires a detection event before water enters the pipes. So the scenario described—opening all heads in a zone to release water upon activation—fits a deluge system.