Dry Powder Fire-Prevention Systems With Impulsive Emission

Our impulsive emission dry powder extinguishing systems are of a particular type of powder system. Indeed, they are characterised by the fact that the system is no longer pressurised by a battery of cylinders but by micro-charges of aerosols incorporated into the powder tank itself. Savings in terms of weight and space for the system are thus achieved.

COMPONENTS

The units in question are composed only of:

• One or more steel modules containing both the dry extinguishing powder and the micro-charge of condensed aerosol (compound) that pressurises the system if necessary;
• Possibly a series of pipes for transporting the powder;
• Discharge nozzles.

Furthermore, the system can be composed of “stand-alone” modules positioned on the ceiling in the environment to be protected, without the need for pipes or nozzles.

The module is in a non-pressurised rest state, whilst in the event of an alarm, a voltage signal from the fire detection and extinguishing control unit triggers the aerosol compound. The activated compound starts aerosol production, which causes a rapid increase in pressure inside the powder tank. When the pressure inside the casing exceeds the nominal rupture value of the protective membrane, the powder is discharged through the nebuliser nozzle, almost instantaneously.

FIELDS OF APPLICATION

The modules are intended to suppress and extinguish fires of solid materials, flammable liquids and electrical equipment in closed, semi-closed and open environments and are designed for use with relative air humidity up to 95%, with strong vibrations and aggressive environments. They are utilised in warehouses, deposits of flammable liquids, archives, engine rooms, machine rooms, and so on.

The powders released fight the fire with an anti-catalytic, fuel-combustive separation and cooling action.

ADVANTAGES AND DISADVANTAGES

Advantages

• Extreme versatility due to being effective on any class of fire, so long as the appropriate type of powder is used;
• Very low cost;
• Rapid fire suppression;
• Compatibility for use also with other extinguishing agents;
• Zero electrical conductivity, for use even on electrical equipment in operation;
• No thermal shock;
• A reduction in space and weight compared to a traditional powder system;
• Flexibility for any reduction/expansion of the system over time, as such requires merely eliminating or adding further modules to the environment;
• No need for high pressure cylinders;
• Reduced maintenance thanks to the fact that there are no canisters under pressure.

Disadvantages

• They require intense cleaning of the premises following discharge, which in any case involves the simple vacuuming of the dry powder;
• Deterioration over time of the effectiveness of the powder, which must be replaced periodically;
• ABC powders can generate HF phosphoric acid in the event of contact with water and thus the corrosion of equipment;
• The discharge of the powder causes risks such as reduced visibility and temporary breathing difficulties, hence adequate means of signalling must be installed to ensure that personnel can evacuate the area prior to discharge;
• Dimensional restrictions on the length of tubing that can be used.

To guarantee perfect functionality, the dry powder extinguishing systems we design and install can be subjected to numerous and customisable maintenance and monitoring schedules offered through our Service.