A product-of-combustion (heat, smoke, or flame) detector senses the presence of a fire condition.

An individual working in the area discovers a fire in progress.

The fire detection system sends a signal to the deluge valve, causing the valve to open.

The individual who discovers the fire manually trips the deluge valve.

As water enters the deluge valve and the piping, water flow indicator alarms are transmitted to signaling stations, and the water motor gong (if present) is activated.

Water flow through all open sprinklers simultaneously.