Alternative non-polluting gases:
There are two groups: Halocarbon (of the HFC, HCFC, PHC type) and inert gases (Argon, N2 or mixtures of them).
- Inert gas systems: These systems use rare gases or their mixtures, which reduces the cost with respect to systems using halocarbon gases. However, as they function at higher concentrations, they require a larger number of cylinders. Their main advantage is the low cost of re-filling. Another advantage is the fact that they do not damage the environment since their ambient warming coefficient is zero.
- Argon (IG-01) Fire Extinguishing Systems: This is a mixture and a non- patented product, which makes it a very popular gas in Turkey. It has no global warming effect. One can use it safely even at locations where human beings are present. It is used to replace Halon 1301 gas in the extinguishing systems. It is suitable for a cylinder pressure of 200 or 300 bars and an installation pressure of 50-60 bars. It has a discharge time of 60 seconds. This is not a gas mixture. It has a low cost of refilling. It is available and can be used in refilling locally.
- Fire extinguishing systems with Halocarbon-based gases: The most widespread halocarbon-based gases used as extinguishing chemicals are: HFC23 (FE13), HFC125, HFC227. They extinguish fire by chemical and physical action. They merge with radicals released during a fire and absorb the heat, which extinguishes the fire.
- FE13 (HFC23): This offers a safe use in the presence of humans. It is suitable for a cylinder pressure of 42 bars and has a discharge time of 10 seconds. The manufacturer is the company DUPONT. It does not damage the ozone layer.
- HFC227 ea: This offers a safe use in the presence of humans. It is suitable for a cylinder pressure of 25 bars or 42 bars and has a discharge time of 10 seconds. It is also available under the commercial names FM200, FE227, NAFS227 and HFC227.
- HFC125: This offers a safe use in the presence of humans. It is suitable for a cylinder pressure of 25 or 42 bars and has a discharge time of 10 seconds. It is also available under the trade names FE25, NAFS125 and HF125.
Particularly the gas HFC125 constitutes a good alternative for the replacement of cylinders and nozzles and for the renewal of old systems since it permits to use the same pipes as the existing ones used with Halon 1301
- Fire extinguishing systems using CO2: This is not a fire extinguisher of the class of non-polluting gases. It extinguishes the fire not chemically but physically. It can be used to extinguish superficial or internal fires. It cannot be used in the presence of humans. It is suitable for a cylinder pressure of 50 bars. With its low cost of refilling, it is economical. It has a discharge time of 60 seconds. It is widely available and refilled locally.
|
Gas |
FM 200 |
FE 13 |
Argon |
Carbon dioxide |
|
Chemical name |
Heptafluoropan |
Trifluoromethane |
Argon |
Carbon dioxide |
|
Formula |
CF3CHFCF3 |
CHF3 |
Ar |
CO2 |
|
Molecule weight |
170 |
70.01 |
39.9 |
44.01 |
|
Boiling point °C (1.013 bar) |
-16.4 |
-82.1 |
-186 |
- |
|
Density (20 °C) kg/m3 |
1.407 |
807 |
* 200 bar (max. refilling density) |
777 |
|
Critical temperature °C |
101.7 |
25.9 °C |
-122 |
31 |
|
Critical pressure (bar) |
29.12 |
48.36 |
49.03 |
73.82 |
|
Design concentration (%) (Heptane) |
8 |
18 |
46 (extinguishing concentration) |
- |
|
Flooding Factor (Heptane) |
0,634 kg/m3 |
0,664x1.2 kg/m3 |
* 0,616 m3/m3 |
- |
|
Extinguishing concentration (%) (Class A) |
7 |
18 |
36 |
* 34 (superficial type) |
|
NOAEL (%) |
9 |
50 |
43 |
- |
|
LOAEL (%) |
10.5 |
>50 |
52 |
- |
* Comparison between different criteria
Operating principle of the system of electronic detection and automatic fire extinguishing with gas
The principle of automatic fire extinguishing systems using gas consists of the activation of the fire extinguishing system by alarm signals coming from sensors using different operating principles installed in accordance with the cross-zone principle.
To improve the reliability of the system, the system is installed so there are 2 different channels in accordance with the cross-zone installation principle as described above by means of ionization or optic smoke sensors that detect smoke by means of different principles and that are connected to the control panel of fire extinguishing.
Whenever an alarm signal is received from a sensor, it is identified as a preliminary alarm and the fire extinguishing system is not activated at that stage. This prevents wrong detections causing unnecessary discharges. At places where fire extinguishing is required, there is a sound/light alarm device that indicates that the fire extinguishing function is active and that the gas is ready to be discharged. It is possible to start the fire extinguishing system mechanically (manually). It is also possible to stop the system manually.
The system is designed to have a total gas discharge in less than 10 seconds. All nozzles and other equipment are selected in accordance with that feature.
Our company provides and installs products of the brands TYCO and LPG in gas-using fire extinguishing systems and of the brands NOTIFIER by HONEYWELL in electronic sensors in the field of fire fighting systems depending on the requirements of the customer and the compatibility of the products with the proposed solution.
Our sales engineers look forward to your invitation to carry out a free cost assessment to find the best solution according to your project and your budget in the field of automatic fire extinguishing systems.