Inert gas fire suppression systems are used as “clean agent” fire suppression systems in accordance with the standards NFPA 2001 and ISO14520. The principle of extinguishing a fire is to introduce inert gases in the protected zone and to reduce the concentration of oxygen, i.e. to quench the fire. It is used as a safe and efficient agent to extinguish Class A fires (solid materials), Class B fires (flammable liquids) and Higher Hazard Class A fires (solid materials energized with electricity during the extinguishment period).

IG 55 fire suppression system extinguishes a fire using a combination of inert gases 50% nitrogen and 50% argon.

Inergen (IG 541) fire suppression system uses a combination of inert gasses: 52% nitrogen, 42 % argon and 8% carbon dioxide. Inergen fire suppression systems have carbon dioxide added to them for the purpose of adaptation of the human body when inhaling the air with a reduced quantity of oxygen. When carbon dioxide is present in the air, the human body increases air intake (deeper and faster breathing). In this way the body is supplied with greater quantity of air and, accordingly, greater quantity of oxygen.

An Inergen / IG55 fire suppression system is especially suitable on account of the following:

  • design concentrations of atmospheric gas are not harmful to human health,
  • high fire extinguishing efficiency,
  • very rapid action,
  • minimum reduction of the visual range during fire fighting,
  • maximum dispersion of gas in the protected room,
  • good mixing of gas with air,
  • the gas is noncorrosive, electrically non-conductive and does not cause cold shocks to electronic devices,
  • the gas is highly environmentally acceptable
    • does not deplete the ozone layer (ODP = 0 / Montreal Protocol)
    • does not heat the atmosphere (GWP =0 / Kyoto Protocol)
    • atmospheric lifetime is instantaneous (since argon and nitrogen are component parts of the air)


  • ISO code: IG541 (Inergen) / IG55
  • ODP (Ozone depletion potential) 0
  • Atmospheric lifetime: instantaneous
  • NOAEL 43%
  • LOAEL 52 %
  • GWP (Global warming potential) 0
  • Safety level (Class A firer) 6.8%

Inergen and IG 55 fire suppression systems have no environmental pursuant to either the Montreal Agreement or the Kyoto Protocol.