High pressure extinguishing system
A high pressure extinguishing system (abbreviation: HDL, especially in Austria also called maximum pressure extinguishing system ) should achieve the greatest possible extinguishing effect with as little water as possible . The principle of a high pressure extinguishing system is that "the finer the water droplets - the faster the water evaporates - the better the extinguishing effect ". Water that does not evaporate is, in terms of extinguishing technology, "waste" and is responsible for the notorious water damage in what is actually a small fire .
In contrast to a pulse extinguishing system, a high pressure extinguishing system emits a constant jet, but both work, depending on the type, with pressures above 100 bar . Thanks to the ultra-fine atomization, the surface of the extinguishing agent (water with or without foam compound ) is suddenly and massively enlarged, so that it evaporates more quickly . Special features are the fast and highly efficient evaporation, which extracts the enormous amount of heat of 2.3 MJ per liter of water from the environment. Likewise, when it hits the flames, the air is displaced by the direct evaporation (approx. 1600 times the volume of the original water droplet), which enables the flames to be contained quickly. In addition, there is an enormous cooling effect and efficient shielding from radiant heat for surrounding fire loads and people in the vicinity.
Mobile high pressure extinguishing systems
Mobile high-pressure extinguishing systems are a further stage in the development of extinguishing technologies; they are intended for fighting small and vehicle fires. Due to the fine atomization, however, the throwing range of the jet is small, so that it is necessary to act relatively close to the source of the fire and is therefore not suitable for an external attack.
In the case of a high-pressure extinguishing system on a fire engine, the fire brigade uses approx. 40 to 200 bar and a water volume of approx. 20 to 150 l / min depending on the system and jet pipe (otherwise approx. 200 to 800 l / min with C / B pipe ) worked. The systems are designed for a quick initial attack with small amounts of water and are primarily used to fight small and vehicle fires while minimizing water damage.
The main assemblies are essentially a high-pressure pump , the drive (not applicable if permanently installed in the vehicle), the water tank and a hose reel with a special jet pipe.
High-pressure extinguishing systems are particularly suitable for an internal attack: the fine water mist and the small amounts of water enable effective and rapid fire fighting.
Mobile high-pressure extinguishing systems are dependent on the supply of extinguishing water via appropriate HP pumps and lines suitable for high pressure. You are therefore tied to their range (usually 40 to 80 meters).
The portable high-pressure extinguishing systems do not need any pumps or pipes, the amount of water is limited to a few liters, but this is due to the fast attack time and the particularly effective extinguishing technology (extinguishing water is mixed with compressed air sprayed at approx. 200 bar or higher) - especially with apartment fires in the early stages - sufficient and thus excludes water damage.
Two types as an example:
- "UHPS - Ultra High Pressure System" from Rosenbauer
- "HDL 250" from Minimax