WATER MIST FIRE SUPPRESSION SYSTEMS
Our company carries out all design, installation and maintenance operations for high-, medium- and low-pressure automatic water mist systems. The water mist system must be built in respect of the design and installation parameters emerging from the full-scale tests for scenarios similar to that to be protected.
HOW WATER MIST TECHNOLOGY WORKS
A water mist system utilises water in the form of very dense fog in order to either contain the fire underway or otherwise completely extinguish the breakout, depending on the design scenario under consideration. The use of extremely micro-drops with a minuscule diameter guarantees a much higher efficiency than traditional water systems, since the same volume of water in micro-drops has a greater total specific surface. This translates to a greater cooling capacity over the fire and local inertisation by reducing the amount of oxygen around the fire.
COMPONENTS OF A WATER MIST SYSTEM
The system, being very similar to a classic sprinkler, is generally characterised by the following main components:
- Water supply (accumulation tank, tank, etcetera) generally with a smaller capacity;
- Pumping unit or battery of cylinders;
- Collector and distribution network for the water;
- Dispensing nozzles.
Water mist nozzles can be of the closed type with thermally-activated bulb (that activates when the temperature reaches a certain limit value, just like the sprinklers) and triggered when the temperature reaches a certain limit value (just like the sprinkler nozzles) or else can be of an open type that drains the water from all heads installed at the same time, following a command to activate the detection and extinguishing system.
The nominal operating pressure varies according to the type of system, which can be of low-pressure (<12.5 bar), medium-pressure (> 12.5 bar and <35 bar) or high-pressure (> 35 bar, with a typical value of 100 bar) and are guaranteed by a specially-created pumping unit or, for smaller systems, by a battery of nitrogen and water cylinders.
ADVANTAGES AND DISADVANTAGES
Advantages
- Minimum impact on the goods and materials kept in the protected spaces, as compared to a sprinkler system;
- There is no danger to people in the environment since the extinguishing medium is simply water, thus pre-alarm systems are not strictly necessary as they would be for inert gases or aerosols;
- Minimal cleaning operations, due to the lower quantity of water discharged into the environment;
- Small-scale water storage tanks and pump rooms;
- The use of stainless-steel pipes with extremely small diameter (12–50 mm).
Disadvantages
- Higher costs than a sprinkler system;
- Complicated system design as it depends on the specific certifications of the manufacturer;
- For systems with cylinders, when the supply of nitrogen and/or water runs out, the system will no longer be able to guarantee continuous extinction in the event of a fire that is out of control.
FIELDS OF APPLICATION
All these features render water mist systems suitable for mechanical rooms with gas or steam turbines, transformers, electrical substations, for shipyards, road and railway tunnels, industrial kitchens, archives and libraries, high-rise buildings, hospitals, car parks, buildings of historical and cultural importance, with diesel engines and alternators.
COMPATIBLE WITH WATER MIST SYSTEMS
The water mist extinguishing systems can avail of small-scale thrust units and accumulation tanks for pumping and storing water. Moreover, to guarantee the highest degree of efficiency and safety, they can be combined with smoke-detection systems and be subject to the various maintenance offerings in our Service.
Types of fire-fighting systems
Our Aerosol extinguishing systems are efficient, free from environmental impact and competitive on the market due to their swift design, installation and maintenance.
Carbon Dioxide (CO₂) systems are simple, reliable and effective. Being easy to manage and maintain, they offer total safety even in large industrial production spaces.
Our inert gas systems use Argon and Nitrogen which, due to their nature, offer complete safety even on particularly delicate and precious materials.
Dry powder extinguishing systems, in particular with Sodium Bicarbonate, are ideal for extensive sites in the petrochemical industry.
Water Mist extinguishing systems are efficient, having no environmental impact and being non-toxic, offering a high extinguishing power thanks to the elevated pressurisation of the water that is not released as a “deluge” but is sprayed.
In the event of fire, these active safety systems guarantee the escape of any smoke from the safeguarded rooms, produced by the combustion in the areas at risk. With this mode, the SistemOpen90°™ ensures the areas are safe and smoke-free, guaranteeing the area leading to the escape routes is protected.
Designed to suppress and extinguish fires of solid materials, flammable liquid fuels and electrical equipment.
Foam Systems avail of a mixture of water and foam to extinguish fires and are particularly appropriate in the presence of flammable liquids.
For all systems using water as an extinguishing agent, these guarantee that the flow rate is exact so as to ensure perfect efficiency and reliability.
ESSECI S.r.l. offers an instrumentation rental service and performs tests directly with its own qualified technicians. On request, a Test Report signed by a Fire Prevention Expert can also be issued.
In the event of a fire, active safety systems guarantee a higher pressure in the safeguarded premises than in the other environments. In this way, they keep the safeguarded areas constantly free from smoke, creating a protected area leading towards the escape routes.
Our smoke and gas detection systems, with the relative alarm signalling systems and any extinguishing units, guarantee full protection against the risk of fire.
Integrated detection, video monitoring and extinguishing systems with remote control for the open-air storage of various kinds of flammable materials.