Which gas is used in fire extinguishers

Which fire extinguisher is right for me?

Unfortunately, the classic fire extinguisher - one for all - does not exist. The market offers several types of fire extinguishers. In order to find the right one for the respective / my purpose, the following 2 main criteria must be taken into account:

1. Fire classes

All flammable substances are divided into so-called "fire classes". First you should filter which fires of the 5 fire classes you can expect.
Here is an overview with the subdivision of the 5 fire classes:

Attention for class C fires (gases): The most important measure in this case is to cut off the gas supply !!! Extinguishing the source of the fire is not very promising if the supply has not been stopped beforehand. If the fire is extinguished with a fire extinguisher, for example, gas continues to flow out. A new fire or even explosion hazard arises and the situation may get out of control.

2. Extinguishing media

Since the individual fire classes have different combustion properties, the right extinguishing agent is of the greatest importance.
Here is an overview of the different extinguishing agents, their (brief) description and their suitability according to fire classes. Select the extinguishing agent that best suits your purpose.
You can read the exact description and functionality of the respective extinguishing agent in the "Extinguishing agent" section - here

Artdescription

POWDER

 

ABC powder fire extinguisher (ember powder) - the all-round extinguisher
Extinguishers with ember fire powder are generally suitable for extinguishing ember fires. The melting of the powder on the material to be burned creates a barrier layer which makes re-ignition more difficult.

Extinguishing effect: Disruptive effect, embroidery effect
Frost-resistant: up to - 30 ° C; Code letter: G
Suitable for fire class: A, B and C.
 

BC powder fire extinguishers (flame powder) - only to be found on the market as special extinguishers
Flame fire powder can only be used to fight fires in the flame fire phase, i.e. if no glowing zones have yet formed.

Extinguishing effect: Disruptive effect
Frost-resistant: up to - 30 ° C; Code letter: P
Suitable for fire class: B and C
 

Powder extinguisher with metal fire powder - the special extinguisher for metal companies
Extinguishers with metal fire powder are specially designed only for fires of metals.

Extinguishing effect: Embroidery effect
Frost-resistant: up to - 30 ° C; Code letter: M
Suitable for fire class: D

FOAM

 

Foam fire extinguisher - the clean one
They are used to fight fires of solid substances burning with embers and flames as well as liquid substances. Foam extinguishers cause far less damage to extinguishing agent residues than powder extinguishers. The foam cover on the material to be burned creates a barrier layer which makes re-ignition more difficult.

Extinguishing effect: Embroidery effect, cooling effect
Frost-resistant: no, only with additives; Code letter: S
Suitable for fire class: A and B

Grease fire extinguishing agent

 

Grease fire extinguisher - the household extinguisher
The grease fire extinguishing agent is an aqueous extinguishing agent and the extinguishing effect is based on saponification (hydrolysis of an ester), which results in salts. The extinguishing agent forms a barrier layer over the oil or fat, thereby preventing the absorption of oxygen. At the same time, the extinguishing agent cools the burning liquid below the auto-ignition temperature and thus prevents the fire from flaring up again. In summary, it is the only effective extinguishing agent against fat fires, which is very effective and is conditionally also suitable for fires of fire class A and B.

Extinguishing effect: Embroidery effect, cooling effect
Frost-resistant: no, only with additives; Code letter: F
Suitable for fire class: A and F (but also possible as A, B and F)

CO2 / carbon dioxide

 

CO2 fire extinguisher (carbon dioxide extinguisher) - the one for sensitive areas of application
The gas carbon dioxide is used as an extinguishing agent. Carbon dioxide is a definite flame extinguisher with no long-term effect. It is therefore suitable for fighting small liquid fires such as gasoline and kerosene as well as for electrical systems and gases escaping under pressure (e.g. propane). The carbon dioxide extinguisher is not suitable for ember fires and has no effect against possible re-ignition.
As the liquid carbon dioxide flows out of the pressure vessel, a strong cooling occurs which, depending on the given conditions, can be so great that the freezing point of the carbon dioxide (-78.5 ° C) is reached. Therefore, never point a CO2 extinguisher at people or animals !! Be aware of your own risk of suffocation in the surrounding area!

Extinguishing effect: Embroidery effect
Frost-resistant: up to - 30 ° C; Code letter: K
Suitable for fire class: B (formerly also C)

WATER

 

Water fire extinguishers (formerly wet extinguishers) - hardly to be found on the market anymore
In the case of the wet extinguisher, water is used as the extinguishing agent. In some cases, antifreeze or wetting agent is added to the water. The wet extinguisher has an output of 5-6 l / min at a throwing height of 6m and a throwing distance of 10m. It causes the flammable material to cool down. It is suitable for combating solid substances that are burning with embers and flames.

Extinguishing effect: Cooling effect
Frost-resistant: no, only with additives; Code letter: W (formerly N)
Suitable for fire class: A; Warning, dangerous in class F and D!


Note that the powder extinguishing agent spreads very easily and can be found on walls, upholstered furniture, textiles, etc. sticks very strongly. Therefore, before using it, make sure that nobody is in the affected room and that you can still find the exit yourself in the powder mist! In addition, it is advisable to use foam extinguishers instead of powder extinguishers, especially in living areas. These are a bit more expensive, but especially with small fires, the damage is not increased by the use of powder!
When buying handheld fire extinguishers, pay attention to the type of extinguishing agent! Especially cheap offers in hardware stores are often powder extinguishers.