In the open head sprinkler configuration, what happens when the system is activated?

• A. All heads spray when activated
• B. Only heads opened by heat spray
• C. No heads spray
• D. Heads require manual activation

Answer: (A)

In an open head (deluge) sprinkler configuration, all sprinkler heads are open to the water supply. When the system is activated, water flows to every head in the network, so every head sprays at once. This design is used when immediate, whole-area coverage is essential, such as in high-hazard zones where rapid suppression is critical. Unlike systems where only heated or individually activated heads release water, the open-head setup ensures there are no holdbacks at any head.