Design of gas extinguishing systems

The Novec™ 1230 extinguishing gas was developed as an alternative to Halon 1301 as its production was discontinued at the end of 1993, in accordance with measures adopted in the Montreal Protocol of November 1992. The Novec™ 1230 does not contain bromine or chlorine, and therefore, has no ozone depleting potential. One or more extinguishing cylinder may be installed in the Novec system to supply the protected area with a predetermined amount of gas.

The extinguishing cylinder is designed to hold the Novec gas in a liquid state, and the nitrogen gas container above the liquid keeps the reservoir pressurized at 25 bar or 42 bar (at 20 °C).

Under normal conditions, the Novec™ 1230 is a colourless liquid with a slight characteristic odour and a density of approx. 11 times the density of the air. It does not contain solid particles or oily residues. It is produced according to the ISO 9001 guidelines, under strict production standards that guarantee the purity of the product.

The Novec™ 1230 extinguishes fire by absorbing heat and chemically interfering with the combustion reaction. During extinguishing, the Oxygen concentration remains at about 16–20% and the concentration of the extinguishing agent in the room does not exceed the NOAEL (detection of harmful toxic and physiological effects).

Novec decomposes at 500 °C, so it is important to avoid use in risk scenarios where continuous hot surfaces can be expected. Upon contact with fire, the Novec™ 1230 is decomposed to halogen acids, however, fire-toxicological studies have concluded that fire-generated combustion products—especially carbon monoxide, smoke, heat and the lack of oxygen—present greater risks.

The extinguishing agent required for flooding the protected space in a predetermined concentration is stored in solenoid-triggered welded cylinder at 25 or 42 bar operating pressure.

The actuator assembly is responsible for supplying extinguishing gas to the distribution pipeworks after manual or electrical start.

The extinguishing agent enters the protected space from the extinguishing agent storage tank via hydrodynamically sized, fixed steel pipeworks.

The purpose of the nozzles is to transfer the extinguishing gas into the area to be extinguished. The extinguishing gas is in a liquid state in the cylinder and in the pipeworks; it becomes gaseous as a result of the sudden pressure drop at the nozzle.

The overpressure relief built into the wall is responsible for releasing the overpressure from the room when the Novec extinguishing gas is released into the protected area in the event of a fire.

• Novec1230 does not damage the ozone layer
• It does not contain bromine or chlorine
• The gas allows immediate intervention against fire
• Do not exceed NOAEL and LOAEL limits
• No need to clean the room after extinguishing
• Suitable for extinguishing most types of fires
• Not electrically conductive

• protection of computer rooms, control rooms
• laboratories
• call centres
• in spaces where flammable liquids are stored
• oil switchgear
• transformer stations
• nuclear power plants
• sites containing radioactive substances
• electrical equipment
• museums, libraries, archives

The main components of the INERGEN gas mixture—Argon (40%), Nitrogen (52%) and Carbon dioxide (8%)—are naturally occurring gases. This gas mixture is excellent for extinguishing living areas. It has no ozone depleting effect and is neutral in terms of the greenhouse effect. Its chemical state is stable, it is not conductive and not corrosive. When the system is triggered, the released gases simply occupy their natural place in the atmosphere after extinguishing.

The design aims to reduce the concentration of Oxygen in the protected space to between 10% and 13% to prevent combustion.

After the extinguishing is started, the INERGEN gas is distributed evenly over the area to be extinguished. The concentration required for extinguishing should be reached within 60 seconds. In the vicinity of the outflow, the cooling caused by the depressurized gas is very intense, so direct contact with the outflowing gas should be avoided. May cause frostbite on the skin surface.

In order to ensure the basic condition for gas extinguishing, the gas should be retained in the protected space for a minimum of 10 minutes.

The room must be evacuated during the arbitrarily specified time period between the fire alarm and the extinguishing. After the delay period, the starter extinguishing gas discharge valve receives a start signal from the extinguishing control centre, which causes it to open, thereby opening the way for the extinguishing gas through the pipeworks to the nozzles installed in the room to be protected and actuating the other valves. In the event of flooding with extinguishing gas, a warning light gives warning at the entrance. Within the delay period, the “Extinguishing inhibitor” push button located at the exit of the room can be used to disable the extinguishing gas outflow if the person in charge is certain that the extinguishing is unjustified (e.g. false alarm, fire extinguished, etc.). The manual “Start extinguishing” button installed at the entrance to the room can be used to start the inflow of the extinguishing gas into the protected room immediately without delay.

The extinguishing agent required for flooding the protected space in a predetermined concentration is stored in welded cylinder of INERGEN make at 300 bar operating pressure.

The purpose of the flood valve is to supply the extinguishing gas to the distribution pipeworks after manual, electrical or pneumatic actuation.

The connection port on the flood valve functions as both inlet and outlet, so the same connection is used for the pilot and the slave cylinders.

The flood valve is connected to the distribution pipeworks via a flexible pipeline.

The extinguishing agent enters the protected space from the extinguishing agent storage tank via hydrodynamically sized, fixed steel pipeworks.

The purpose of the hydraulic calculation is to discharge the target volume at each nozzle, 95% of the extinguishing should be introduced into the space to be extinguished within the intended discharge time (60 s).

The purpose of the nozzles is to transfer the extinguishing gas into the area to be extinguished. The extinguishing agent travels in a gaseous state in the pipeworks and introduced via sized nozzles.

The pressure relief built into the wall is responsible for releasing the surplus air from the room when the INERGEN extinguishing gas is released into the protected area in the event of a fire. This is achieved by a spring-loaded mechanical locking mechanism which opens under pressure.

The pressure relief can prevent flames and smoke from entering the protected space for 60 minutes using a heat-activated sloughing material.

The attenuation units mounted on the nozzles reduce the vibrations caused by the pressure wave of the extinguishing gas outflow.

• INERGEN® offers an environmentally friendly fire protection solution that does not damage the ozone layer. After release, the gases simply occupy their natural place in the atmosphere
• The gas allows immediate intervention against fire
• Does not contain harmful substances
• Inergen does not produce decomposition products
• Provides a maintained 3D extinguishing effect
• A well-documented extinguishing agent that is not harmful to health
• It is possible to conduct a real 1:1 fire test
• No need to clean the room after extinguishing
• Suitable for extinguishing most types of fires
• The design of a system within a given volume is independent of its design and equipment
• Good visibility is maintained during extinguishing facilitating safe escape
• The Inergen extinguishing system ensures that the people receive enough oxygen during the fire even when they are indoors

• protection of computer rooms, control rooms
• laboratories
• call centres
• in spaces where flammable liquids are stored
• oil switchgear
• transformer stations
• nuclear power plants
• sites containing radioactive substances
• electrical equipment
• museums, libraries, archives