Teknik

Water mist under high pressure. How does it operate?

Fogmaker high-pressure water mist extinguishes fires with the help of three basic mechanisms. All three operating modes depend on the size of the drops.

The high pressure, 100 bar, and special nozzles break the water down into very small drops. The average size of the drops is 50 µm. As a simple comparison, 8,000 of these small drops are the size of one drop with a 1 mm diameter!

One litre of water requires 335 kJ in order to be heated up from +20 to +100° C and a further 2,257 kJ in order to turn from water into steam. As far as heat absorption ability is concerned, water is the best extinguishing agent that can be used in a sprinkler system.

Upon vaporisation, 1 litre of water expands to 1,700 litres of steam. The oxygen content is reduced very effectively and smothers the fire from its centre, where the oxygen content is at its lowest and prevents new oxygen from being added.

Besides water, the extinguishing agent also contains antifreeze and AFFF, a foam maker which is a very effective extinguishing agent for fire in petrol, diesel or oils

PATENTED HIGH-PRESSURE TECHNOLOGY.

Fogmaker has developed a extinguisher with high pressure (100bar) that functions like a piston accumulator.

Water mist under high pressure is known to be a superior firefighter media in engine compartments. The high pressure combined with the special spray nozzles create micro drops with an average size of of 5µm. As a comparison, there are 8000 of these micro drops to one drop with a diameter of 1mm.

The small water drops are immediately vaporized in contact with heat. In connection with the vaporization, 1 liter of water creates 1700 liters of water mist. The water mist increases the water content of the air and prevents new oxygen supply to the fire. In the vaporization process the water mist cools the smoke gases and hot objects in the engine compartment.

It takes 1 calorie of energy to heat 1 gram of water to+1ºC, and 540 times more calories to heat the same quantity of water into steam. The rapid heat absorption enables the Fogmaker system to reduce the heat and this effective cooling contributes to the rapid extinction of the fire and reduces the risk for re-ignition. The water mist also includes an addition of foam that lays a cover over inflammable oil products that tend to collect in engine trays.