Which type of standpipe system requires a supplemental detection system?

A preaction standpipe system requires a supplemental detection system because it is designed to integrate both fire detection and suppression features. In a preaction system, water is not released into the pipes until there is confirmation of a fire through the activation of a detection system. This two-step process helps prevent water damage that could occur if there is a false alarm or the system is activated without fire conditions present.

The integration of detection ensures that water flow is only initiated when the fire is confirmed, making it particularly suitable for areas where the risk of unintended activation must be minimized, such as in data centers or areas housing sensitive equipment. This characteristic of requiring supplemental detection is key to its effective functioning and differentiates it from other standpipe systems that may not require such a mechanism for operation.