More and more companies are specializing in the production of cables for industrial and private use to be used for the most varied uses: most electrical and industrial cables are made with the addition of halogens, ie elements such as fluorine, chlorine, bromine, iodine which have special properties combined together with metals, creating salts, hence the name of halogens.
They are present in most PVC composite cables, in those with fluorinated resins and in all those elements that have the property of delaying the spread of the flame.
When a fire should occur in an environment that also involves cables, these elements have the characteristic of acting as radical collection centers, trying to limit the increase in combustion.
Despite having this retarding power in the propagation of flames, at the same time they capture hydrogen, giving rise to a toxic substance, hydrogen halide. Not surprisingly, the most relevant effects are given by:
● corrosion of metals
● damage to organic materials
● generation of highly toxic fumes
Precisely for this reason, in the last few years halogen-free cables have been increasingly used, much safer for both man and the environment. We try to better understand what it is and what their characteristics are.
Halogen free cable: features and properties
As it is easy to understand, the main characteristic of this type of cables is that of possessing a structure composed of halogen-free materials. The precise name of this type of cable is “low smoke zero halogen” and are generally identified with the acronyms LSOH, LS0H or LSZH.
Thanks to the absence of these elements, if a fire breaks out they guarantee an extremely limited emission of opaque fumes and potentially toxic and corrosive gases. They are ideal to be installed in all environments in which particular conditions can give rise to phenomena of self-combustion and consequently cause the emission of toxic fumes.
Prolonged exposure of a person to these fumes or gases can lead to serious health problems or even be fatal, especially when working in closed and poorly ventilated areas.
How to recognize halogen-free cables
The abbreviations, or rather the acronyms, that we have indicated above allow you to quickly identify this particular type of cable and are usually laid so as to ensure maximum insulation, precisely to avoid the dangers of possible combustion.
One of the most interesting aspects of halogen-free cables is the fact that there is a specific and rather stringent standard that requires to carry out a whole series of checks on these products before putting them on the market. These checks, as mentioned, are not carried out on the basis of a business choice but are dictated by the following European regulations:
● CEI EN 60332-1-2
● CEI EN 50267-2-2
● CEI EN 61034-2
● CEI 20-22 / 2
● CEI 20-37 / 3-1
The test that is performed is very simple: try to burn a cable in a test that if it falls within the norm will not spread the flames. This peculiarity guarantees that in a circuit made with such cables, in case of fire, the flames will not affect the entire circuit.
Main areas of use of halogen-free cables
Thanks to their characteristics, halogen-free cables are used in various sectors of activity. Precisely because they have high safety standards, the Ministry of the Interior recommends them for places that are particularly crowded, where works of art and archaeological heritage are exhibited, in all areas where gas is produced and in industrial sectors in general.
Obviously to be sure of making an optimal choice of cables it is advisable to seek the advice of an expert or a valid electrician who can direct the client whether it is necessary or not to use these cables. The only limit that can possibly be found is that halogen-free cables are not identified with a precise color of the covering sheath, and for this reason the presence of a professional who assists the interested party in the choice is necessary.