Gas fire extinguishing system ARGOSYSTEM

The ARGOSYSTEM uses the extinguishing agent argon gas, which acts on the fire by lowering the percentage of oxygen in it from 20.9% to below 15%, which is the threshold below which the fire theoretically goes out. The principle of saturation is total flooding in type, with total saturation. The physical characteristics of the premises to protect are consequently extremely important, so much so that the UNI 10877 standard foresees a pressure test (or more precisely to calculate the leaks), in order to provide an extremely accurate and reliable project.

Argon is an inert gas that humans are used to breathing from birth, since a very small percentage of air is made up of it. Its toxicity has been studied carefully and the standard foresees:

LOAEL, low adverse effects observed level: minimum concentration at which an adverse toxicological or physiological effect was observed. Argon 52% corresponding to 10% of oxygen.

NOAEL, no adverse effects observed level: maximum concentration at which no toxicological or physiological effects were observed. Argon 43% corresponding to 12% of oxygen.

The oxygen concentration will have to:

• drop below 15% to extinguish the fire
• not drop below 12% to allow for human presence inside the protected premises
• if it drops to between 12% and 10%, then discharge delaying devices must be fitted.

Total flooding extinguishing systems are used mainly to guarantee the protection against risks located in the sheathing or equipment featuring a protected volume containing the extinguishing agent, and so they are mainly recommended to extinguish various types of fires:

• Risks inherent to electrical and electronic systems
• For the protection of areas under the flooring or in false ceiling
• Risks inherent to inflammable gases and liquids and fuels
• High value property (such as museums, libraries)
• In premises with expensive instruments and equipment (EDP, control rooms, etc.)

In areas protected by total flooding systems that may be occupied, the provisions set forth by the following safety criteria are applied:

• Time delays
• Automatic/Manual switch and override devices
• Exits, emergency lighting and direction signs
• Automatic closing doors that open outwards
• Visual and acoustic alarms at the exits

Concentration of IG-01 for n-heptane and for risks with class A surfaces