Which type of standpipe system requires a supplemental detection system?

The type of standpipe system that requires a supplemental detection system is the preaction system. Preaction systems are unique because they combine elements of wet and dry systems. They are filled with water only after a fire detection device, such as a heat or smoke detector, has signaled that a fire condition may exist. The requirement for a supplemental detection system is critical because it serves as the trigger for activating the water flow into the system, thus preventing unintended discharge of water in the event of a false alarm.

In this system, the detection devices must be reliable, as the activation of the preaction system is dependent on their detection capabilities. This feature enhances the overall safety and effectiveness of the system in environments where water damage from unintended activation can be costly or harmful, such as museums or data centers.

Other systems, such as dry pipe and wet pipe, do not require supplemental detection systems in the same way since their operation is not contingent on the external detection of fire conditions prior to the flow of water. Deluge systems, while they use open sprinklers that activate simultaneously when the detection system is triggered, do not function based on the supplemental detection in the same manner as preaction systems. Thus, the preaction system distinctly necessitates a supplemental detection system