We provide the right extinguishant for all ranges of application.
Water
Water is mainly used for fighting fire
classification A fires (glowing substances).
The extinguishing effect of water is mainly based on its heat binding capability. The cooling effect of water disturbs the prerequisites of a thermal reaction and hinders further processing of inflammable substances, so that the formation of inflammable gases and vapours is interrupted. Thus, water extinguishes by cooling.
Extinguishing foam and aqueous solutions
Extinguishing
foam is a highly effective mixture of water, foaming agent and air.
A stable foaming agent percentage is added to the water flow with admixture devices. The produced mixture is foamed with air in subsequent foam generators. The foaming degree depends on the capacity of the used foam generator, the foaming agent and the foaming agent admixture rate. In case of a low air intake a wet, heavy extinguishing foam is produced (low expansion foam). If the air percentage is increased, the foam becomes drier and thus lighter (medium and high expansion foam).
The air foam utilizes different extinguishing effects: cooling, suffocating, separating, covering, restraining and displacing - each one alone or together with others they provide a quick extinguishing success.
Film forming foam compounds were developed for fighting fire classification A and B fires. In fire classification A high extinguishing efficiency is achieved with the combination of the cooling effect of water and a high net effect of the AFFF part. In case of liquid fires a very thin sliding film is formed on the burning liquid, which gives the foam excellent flow properties and protects the combustion area from further oxygen supply.
Inert gases
The extinguishing effect of argon,
nitrogen and carbon dioxide is achieved by displacing atmospheric oxygen. This
is called the suffocation effect, which occurs if the value necessary for
combustion falls below the specific limit value. In most cases the fire is
already extinguished in case of an oxygen decrease to 13.8 vol.%. For this the
existing air volume must only be displaced by approx. 1/3, corresponding to an
extinguishing gas concentration of 34 vol.%.
Incendiary matters (e.g. acetylene, carbon monoxide and hydrogen), requiring considerable less oxygen for combustion, require an increase of the extinguishing gas concentration. The extinguishing gases argon and carbon dioxide enter the flooding area very quickly and thoroughly because they are heavier than the ambient air.
Argon (Ar)
is a noble gas obtained from the ambient
air. 0.93 vol.% argon is included in the atmosphere. Its density in relation to
the air is 1.38:1. Being gaseously compressed the extinguishant argon is stored
in high-pressure steel cylinders. The maximum operating pressure is 300 bar.
Argon is not toxic. But during the building-up of the gas concentration
necessary for the extinguishing success, a dangerous situation may arise from
the fire gases and an oxygen deficiency, especially together with a fire.
Nitrogen (N2)
is a colourless, inodorous
and tasteless gas, which is included in the atmosphere at 78.1 vol.%. Its
density in relation to the air is 0.967:1. Being gaseously compressed the
extinguishant nitrogen is stored in high-pressure steel cylinders. At the
moment the maximum operating pressure is 200 bar at an ambient temperature of
+15 °C. Nitrogen is also not toxic, but as for argon a dangerous situation
may arise from fire gases and oxygen deficiency.
Carbon dioxide (CO2)
0.03 vol.% carbon
dioxide is included in the atmosphere. Its density in relation to the air is
1.53:1. Being liquefied under pressure the extinguishant carbon dioxide is
stored in high-pressure steel cylinders (operating pressure at 20 °C: 57
bar) or large low pressure vessels (-20 °C: 20 bar). Due to the liquid
storage a significantly larger extinguishant quantity can be stored requiring
less space. Unlike argon, high carbon dioxide concentrations are unhealthy.
Therefore the trade associations require special protection measures if a limit
value of more than 5 vol.% is exceeded (BGR 134).
Due to its physical characteristics CO2 is the only extinguishing gas, which is also used in hand fire extinguishers.
Extinguishing powder
Extinguishing powders are highly
effective and fast extinguishants. The sudden extinguishing effect of the
powder cloud is caused by the suffocation effect and the, so called,
anticatalytic effect, a chemical intervention into the combustion process. The
formation of melting layers on glowing incendiary matters prevents the
diffusion of atmospheric oxygen and the heat-up of immediate fire surroundings.
Reinflammations are not possible. Extinguishing powders mainly consist of
non-poisonous inorganic salts mixed with waterproofing and pouring agents.
Extinguishing gas Novec™ 1230
The synthetic extinguishing agent 3M™ Novec™ 1230 fire protection fluid is the environmentally compatible alternative. In comparison with chemical extinguishants used so far it has the lowest global warming potential, the shortest atmospheric lifetime and no impact at all on the ozone layer. These positive environmental properties promise above all unlimited use of this extinguishant also in the future.
Novec™ 1230 fluid is neither corrosive nor electrically conductive and causes no damage or residue on sensitive components. It is colourless and essentially odourless as well as liquid at room temperature. The molecules consist of carbon, fluorine and oxygen.
Extinguishing gas HFC-227ea
is an electrically non-conductive odourless and colourless gas. It is stored liquid and under pressure and dispensed into the protected room as a colourless vapour that is clear. HFC-227ea leaves not residue and is well suitable for occupied spaces, since it is harmless for persons at design concentration.
HFC-227ea has the ODP value 0, i.e. it does not reduce stratospheric ozone. The short atmospheric durability of HFC-227ea results from its relatively fast natural degradation.
