This part of ISO 14520 contains specific requirements for gaseous fire-extinguishing systems, with respect to the IG-01 extinguishant. It includes details of physical properties, specification, usage and safety aspects. 2 This part of ISO 14520 covers systems operating at nominal pressures of 160 bar at 15 °C and 200 bar at 15 °C. This does not preclude the use of other systems, although design data for other pressures are not available at this time