Co2 Wheelded fire extinguishers
The main difference between portable and wheelded fire extinguishers is that the seconds, which have a mass exceeding 20 kg, are too heavy to be carried by hand and at the same time manoeuvred easily by one person. However, the trolley fire extinguishers have charge, delivery per unit of time and greater range, so they can extinguish more quickly and with the use of fewer people fires that would otherwise require the contemporary and coordinated commitment of many people with Portable fire extinguishers to be extinct. They are therefore used in cases where the intervention with the portable fire extinguishers proves insufficient.
The classification of the extinguishing capacity of the wheeled extinguishers is regulated by Ministerial Decree 6 March 1992:
' Technical and procedural standards for the classification of extinguishing capacity and for the approval of fire-safety fire extinguishers '
This decree provides that the evaluation of the characteristics and performance, as well as the classification of fire-wheeled extinguishers, are carried out as specified in standard UNI 9492. The same technical standard applies to the formulation of the opinions issued by the Ministry of the Interior for the approval of the fire extinguishers by the Ministry of Merchant Navy.
UNI 9492 defines a wheeled fire extinguisher a "fire extinguisher transported on wheels of a total mass greater than 20 kg and extinguishing content up to 150 kg"
DESCRIPTION OF Co2 FIRE EXTINGUISHERS
In the case of carbon dioxide, the container consists of a normal CO2 tank equipped with a suction pipe that allows the gas to be dispensed in the liquefied state.
The cylinders can be of different capacities, from 18 up to 54 kg of liquefied gas.
Two cylinders connected together can also be mounted on the trolleys. In this case, the extinguishers typically have two 27 kg cylinders, thus a total capacity of 54 kg of extinguish. A high-pressure rubber hose connects the cylinder or the cylinders to a dispensing device equipped with a special diffuser. The handle of the diffusion device is covered with thermally insulating material, because.of the carbon dioxide .
