The basic technology of Cool Gas Generators originates from the solid propellant rocket engines used in the military and space travel. This guarantees a long shelve life time without any maintenance!

1. Principle of operation?

General operating principle; Sodium Azide together with a coolant and a booster are stored pressureless as a ‘chemical grain’ inside the generator and will be initiated by an airbag squib when needed. The squib needs 1.2A for 2 milli seconds to start the decomposition of the chemicals. The chemical decomposition process starts (regardless of the orientation of the generator) through itself using the grain as a coolant and a filter. This allows the (99,7% pure nitrogen N2) to come out at ambient temperature without any residue, diluting the oxygen to a level below 15% where there is no fire possible anymore. The residue from the decomposition of the Sodium azide remains inside the generator and needs to be recycled as normal chemical waste by a certified professional party.

2. Any approvals by likes of UL, FM, VdS, LPCB or CNPP?

Our system has CE certification and is designed to the highest standards. All CNF systems are certified according to Standard for Protection of Electrical Cabinets against Fire (SPECF) standard of CNPP in France. This is a European accredited notiyfing body. We are working on a UL listing for the cool gas generator technology.

3. NFPA compliance and standards followed?

For the EXXFIRE 750/1500/2250 systems there are no applicable standards available, so no compliance to standards is required since it is an additional fire safety product and no mandatory life safety or building safety product. We do try to comply as much as possible to NFPA and NEN norms. Since our product produces IG100 pure nitrogen gas, the NFPA 2001 code applies but the gas storage technology (pressureless) is compliant to NFPA 2010. For Europe, we follow the NEN -EN 15004-8 norms. Design concentration according NFPA 2001 and EN-15004-8 Surface Class A, Higher hazard Class a and Class B.

4. Does it need special provision inside the equipment where it is installed?

No there are no special provisions needed. But for the system to work a (fairly) closed rack or cabinet is required otherwise gaseous fire suppression will not work. The system generates nitrogen (N2) at ambient temperature and low noise level (<99dB). Please contact us for advice on leakage rates.

5. Will it interfere with equipments original functionality in any sense?

No, nitrogen gas at ambient temperature and at a low pressure rate and noise level will have no impact on the functionality of the protected equipment.

6. What’s is the detection method?

The CNF systems have an aspirating smoke detection system using 3 optical sensors for mounting in or outside the protected volume using specially in house developed Votexx software to prevent false alarms as much as possible. The TW system range uses a linear heat detection cable in 70 or 105 degrees Celcius.

7. How much time is required for detection?

Depending on the location of the device, though all tests have shown that even in the most remote places of the closed rack or cabinet, smoke was detected within 60 seconds. The linear heat detection cable of the TW will require heat instead of smoke to melt and create a short that triggers the system. So more time will be required to start the extinguishing.

8. How much time is required for extinguishing?

Release time of the Nitrogen gas anywhere between 10 and 20 seconds depending on the size of the generator. This is sufficient according to NFPA 2001 and EN-15004-1.

9. Maximum protected volume, does it includes safety margin for leakages?

The EXXFIRE 1500 produces 1500 liter Nitrogen, if you divide this with the factor (see NFPA 2001 and NEN for calculation tables) that is used to determine the protected volume you reach a protected area of 2.4 m3 of empty space at 20°C Higher Hazard Class A. We use a maximum opening of 324cm2 as leakage factor (same goes for the 750 and 2250 systems). There is a safety margin taken into account if your server rack is filled with equipment. It is however advisable to use this in fairly closed environments to reach the necessary ‘holding’ time of the gas. If this requirement cannot be met, we advise to power down after detection and overspecify the amount of extinguishing gas. This will prevent re-ignition in case of a fire incident.

10. How to test if this product is working?

This technology is approved for Space usage by the European Space Agency (ESA), so extensive test documentation is available. We also did a fair amount of testing with the EXFFIRE 50 (see a test film on our website). The software of the system is doing continuous self checks to see if the system works properly. The CNF system can be disabled by switching the key to Service. The system has still all normal functionalities but will not release the extinguishing gas. This enables full detection and functionality tests.

11. 10 Years is the shelf life but what’s the maintenance schedule?

No maintenance is needed for the generator. The detection system need to be checked annually like all electronics of a fire detection system and the filter of the aspiration system needs yearly replacement. The battery life is 4 years.

12. References of installation.

We have installed already 1500 systems worldwide with over 20 distributors in 40 countries. See for contact details the distributor contact page.

13. Any letter of acceptance from major players like IBM, HP, DELL, WIPRO etc?

Minkels, part of the Legrand group has chosen our system to protect their micro datacenter products being the MatrixCube and MiniCube. We have extensive talks with HP and IBM, we even presented for two R&D forums. As fire suppression technique, Nitrogen is already being accepted and used throughout the world.

14. Any type of post discharge cleaning or testing required for equipment its protection?

None, after deployment of the system ventilation of the protected volume is required.

15. NOAEL and LOAEL.

Same as for other gaseous fire suppression systems using inert Nitrogen gas.
No observed adverse effect level (NOAEL): 43%
Lowest observed adverse effect level (LOAEL): 52%

16. Transport classification

ADR classification 9 with UN3268 for an unused generator. The generators are considered low hazard category 4 which means that you can transport an unlimited amount of kilograms in a normal vehicle equiped with a powder extinguisher of min. 2 kgs, according to the 1000 point table. The generators are packaged in a UN certified packaging and have the appropriate documentation with it. After usage, the generator becomes UN3543 Class 4.2, so normal transportation regulations apply for road and sea only. See also the paragraph about ADR transportation under Resources in the navigation of this website.

17. Operating Pressure and temperature

The pressure inside the generator remains under 40 bar depending on size of the nozzle of the generator. The gas release pressure is under 10 bar. The release time of the nitrogen gas depends on the size of the generator and the chemical composition of the grain, in general anywhere between 10 and 20 seconds. The temperature of the generator becomes 130°C, half an hour after usage. The outside casing of the total system stays below 65°C.