Inert Gas Fire Suppression Systems

These systems are typically used in volumes that house critical equipment or hold sensitive commodities. Because of their rapid response and precise suppression, process downtime and fire damage are kept to a minimum.

In gaseous suppression systems, the extinguishing agent is generally kept in liquid or liquid-gas mixture form under high pressure. Where water-based systems rely on a fire pump to deliver water to the space, gaseous systems carry the extinguishing chemical (gas) to the space using nitrogen or the pressurised gas itself. With systems that protect a single volume and alternative solutions that can protect several spaces from one point, gaseous suppression systems give designers wide flexibility.

Inert gas fire suppression systems are environmentally friendly solutions that work on the principle of smothering a fire by lowering the oxygen level, the essential component of combustion. The gases used in these systems are formed from argon (IG-01), nitrogen (IG-100), carbon dioxide (IG-541), or specific-ratio blends of these (IG-55, IG-541), all of which occur naturally in the atmosphere. Blends such as IG-55 (50% argon + 50% nitrogen) and IG-541 (52% nitrogen + 40% argon + 8% carbon dioxide) are safe for human health: they extinguish the fire by lowering the oxygen level to roughly 12-15%, while allowing brief exposure for people present.

These systems are preferred in critical spaces where water-based suppression could cause damage, such as data centres, museums, archives and electrical switchgear. Compared with chemical gaseous suppression systems, inert gases have no adverse impact on the environment and have zero Ozone Depletion Potential (ODP). Because inert gases do not deplete or degrade over time, they also offer a long-lived suppression solution with low maintenance requirements. Since discharging the gas from the cylinders can cause a rise in pressure, appropriate venting systems and pressure-relief measures are required.