EI FOG "WATER MIST":

EI FOG ’WATER MIST’ is the revolutionary water mist system designed and constructed by the Eusebi group. The extinguishing mechanism on which the Water Mist systems is based is the result of a combination of at least 3 primary effects, which are complementary, and which contribute in different ways to the final control outcome and, very often, to extinguishing the fire too:

• cooling;
• inerting;
• screening of the fire.

The system operates at a pressure of between 100 and 120 bar. The water, which is discharged in minute drops, evaporates when it comes into contact with the fire, taking away heat and thereby controlling it. In addition, the evaporated water droplets are able to absorb infrared radiation, creating a screen and not allowing the heat to be transmitted.

Applications:

• areas in which machines that use fuel are present, cabins, corridors, kitchens and ovens, warehouses and shops inside naval and off-shore units in general;
• computer and telephone rooms;
• in general, it contains the benefits of traditional water and gas systems, which is why it can be applied where the use of one or the other would not have been recommended.

Advantages:

• minimizes the damage caused by the extinguishing agent;
• weights and sizes are minimal;
• very easy to assemble and disassemble;
• eliminates the cost of large storage tanks and pressure groups.

DESCRIPTION OF THE SYSTEM'S COMPONENTS:

Pumping module

The pressure system consists of at least one high-pressure pump (up to 6, depending on the capacity required by the protected area which has been defined as the project area) fitted on a skid.

The water is transported from the pump by means of a check valve in the manifold at the top of the pumping system. A pressure regulation valve, which regulates the excess water by carrying it back to the back-up tank, is fitted to this manifold.

The pressure system manifold is equipped with all the necessary pipe fittings, pressure gauge switches, accumulators and security valves.

When the whole system is at rest, the water is present in the entire network with intact discharge nozzles. A possible fire can cause the bulb of the discharge nozzle to break and the decrease in the system's pressure will be signalled immediately by the low pressure switch, which allows the jockey pump to start.

Back-up tank

The pressure system is connected to a back-up tank which is built with AISI 304 stainless steel plates and section bars.

This is fed by the internal pipeline network.

The level of the water in the tank (minimum storage capacity and too full) is kept under control both by an electrical indicator fitted onto the top of the tank, and by a transparent level indicator fitted on one of its sides. For example, if the water level is at a minimum, the electrical level indicator signals the anomaly to the Control and Command Centre (which then fills the tank up by opening a solenoid valve that is fitted on the tank itself), while the transparent indicator views the on-site situation.

In addition to this, a filter, 2 solenoid valves (one of them as a spare), a ball valve for sectioning, a drain, a vent, an opening for maintenance, an entrance for the system test and an entrance for system overpressure.

Back-up system

The system's propulsion can be either by means of pumps or only nitrogen and water cylinders: therefore, the system can have the pumps to supplement it, or it can itself be the only means of propulsion, thereby allowing any expenses

related to the pump propulsion to be eliminated. In the event of a fire or a malfunction of the main extinguishing system, the back-up system will be activated.

The back-up system is made up of the following main pieces of equipment:

• N2 cylinders;
• H2O cylinders.

The N2 pressurizes the water contained in the cylinders, causing it to flow out and be discharged through the nozzles.

As soon as the nominal rated voltage has been re-established, the solenoids de-energize and return to the closed position.

Once the main system's malfunction has been repaired, the main pump restarts automatically.

Example of typical scaling for normal residential areas and deposits/warehouses