verstikking
By metal fire one understands the uncontrolled and damage causing burning of metals. This is connected with such high temperatures (often over 3000"°C), which makes the employment of water impossible as fire extinguishing agents.
The fire-brigade therefore often fights such fires by suffocating with cement. Very effectively however also the fire fighting with grey cast iron or sodium chloride (thawing salt) proved, which melt over the combustible material and so that a hermetic lining form, which leads to suffocating the fire. Also special metal fire fire-ex. powder (M-powder) can be used, also this consists mainly of salt.
Under any circumstances as fire extinguishing agents water is not suitable with metal fires. Because of the enormously high temperatures with these fires it comes to a chemical fragmentation of the water vapour into hydrogen (detonating gas) and oxygen, so that the fire is additionally strengthened by water. At volume temperatures of up to 1500 degrees approximately 0.2% of the water are split up, up to 2000 degrees 2 per cent and with 2500 degrees already 9 per cent. That means, the hotter a metal fire is, the more dangerously is the employment of water.
