What is a key feature of a preaction sprinkler system?

A preaction sprinkler system is distinct in its design, as it typically contains air in the piping that may or may not be under pressure. This air acts as a buffer to control the system, and the presence of air prevents water from flowing into the pipes until a two-step activation process occurs. First, the heat or smoke detection system must activate, allowing the system to fill with water before it can discharge through the sprinkler heads. This feature is crucial for applications where preventing accidental water discharge is important, such as in areas with sensitive equipment.

The design of the preaction system effectively combines components of both wet and dry systems. It emphasizes reliability in fire detection while maintaining a dry environment in the piping until needed for fire suppression. This provides a level of safety and ensures that water is only discharged when there is a confirmed fire condition, making it particularly suitable for environments that require quick fire response without the risk of water damage from false activations.