Pre-action Fire Sprinkler Systems employ the basic concept of a dry pipe sprinkler system in that water is not normally contained within the pipes. The water is prevented from entering the piping via pressurized air or nitrogen, and an electrically operated valve, known as a pre-action valve.

The system’s discharge is a two-step process: First, the innovative detection system identifies smoke or heat, which activates a pre-action valve that allows water to flow into piping and effectively creates a wet pipe sprinkler system. Second, individual sprinkler heads release to let water flow onto the fire. This second step provides an added level of protection against inadvertent discharge, which makes pre-action systems ideal for water-sensitive environments.

Common installations for these systems include computer rooms, data storage, telecommunications rooms, and fine arts and archival storage.