BS EN 15004‑9:2017 pdf download.Fixed firefighting systems – Gas extinguishing systems.
1 Scope 1.1 This document specifies requirements for gaseous fire-extinguishing systems, with respect to the IG-55 extinguishant. It includes details of physical properties, specification, usage and safety aspects. 1.2 This documents is applicable for systems operating at nominal pressures of 150 bar at 15 °C, 200 bar at 15。C and 300 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.
2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 15004- 1:2017, Fixed firefighting systems一Gas extinguishing systems – – Part 1: Design, installation and maintenance (ISO 14520- 1:2006, modified)
3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 15004- 1 apply.
4 Characteristics and uses 4.1 General IG – 55 is a colourless, odourless, electrically non – conductive gas with a density approximately the sne as that of air. It is an inert gas mixture consisting nominally of 50 % argon and 50 % nitrogen. The mixture specification for IG-55 is as follows: a) argon percentage range (50 +5) % b) nitrogen percentage (50士5) % Extinguishant IG-55 shall comply with the specification shown in Table 1. The physical properties are shown in Table 2. IG-55 extinguishes fires by reduction of the oxygen concentration in the atmosphere of the hazard enclosure. 4.2 Use of IG- 55 systems . IG-55 total flooding systems can be used for extinguishing fires of all classes within the limits specifed in EN 15004 – 1:2017, Clause 4. The extinguishing concentrations and design concentrations for heptane and surface class A hazards are shown in Table 4. The extinguishant requirements per volume of protected space are shown in Table 3 for various levels of concentration. These are based on methods shown in EN 15004- 1:2017, 7.6.
5 Safety of personnel Any hazard to personnel created by the discharge of IG‑55 shall be considered in the design of the system. Potential hazards can arise from the following: a) the extinguishant itself, by reduction in oxygen; and b) the combustion products of the fire. For minimum safety requirements, see EN 15004‑1:2017, Clause 5. Physiological information for IG‑55 is shown in Table 5.
6 System design 6.1 Fill pressure The fill pressure of the container shall not exceed the values given in Tables 6, 7 and 8 for systems operating at 150 bar at 15 °C, 200 bar at 15 °C, and 300 bar at 15 °C respectively.Other pressures can be used and the minimum design pressure specified accordingly. The relationships between pressure and temperature are shown in Figure 1.BS EN 15004‑9 pdf download.