Full Description ADOPTED_FROM:EN 15004-4:2020 This document contains specific requirements for gaseous fire-extinguishing systems, with respect to the HFC 125 extinguishant. It includes details of physical properties, specifications, usage and safety aspects. This document is applicable to systems operating at nominal pressures of 25 bar and 42 bar, superpressurized with nitrogen. This does not preclude the use of other systems.