What characterizes a deluge sprinkler system?

• A. Only one head releases water at a time in a deluge system.
• B. Water is released to only the most severely involved area during an event.
• C. Each head has its own valve that must be opened individually to release water.
• D. All sprinkler heads are open; water is released to all heads when a detection event or control valve is activated.

Answer: (D)

Deluge systems are designed for rapid, full-area sprinkler coverage in high-hazard environments. In this type, every sprinkler head is open and connected to the same water-filled piping. When the system is activated—by a detector or by opening the deluge control valve—water is released to the entire network and comes out of all heads at once. This ensures immediate, universal sprinkler action across the protected space, without waiting for individual heads to be triggered. The design is intentional for situations where quick, widespread coverage is essential, rather than targeting only the most involved area or requiring separate valves for each head.