In past few years, the advancement in Fire safety ‘low smoke’ materials has raised the development of new, safer, non-hazardous equipment in the market. This led to establishment of Low Smoke Cables. The service providers are now advised to install non-hazardous and low smoke cables in public areas and buildings, for the safety of public in case of fire. In case of Fire accidents poisonous gases and dense smoke are produced that dangerously affects the lives of people.
The Low smoke cables produce very less smoke and non-poisonous gases that are safe for the lives of victims of fire accidents. These low smoke cables contain halogen free compounds that produce lesser amount of poisonous and corrosive gases during combustion. They are often installed in poorly ventilated areas and underground tunnel systems. This will reduce the toxic gas accumulation in these areas in case of fire, and will be really helpful in saving the precious lives.
Halogens and their harmful effects
Halogens are name given to a chemical family that includes the chemicals like chlorine, fluorine, bromine, astatine and iodine. These halogens are widely used in our various daily-use products because of their flame retardant nature. They are also present in PVC (polyvinyl chloride), which is a coating that makes up cable jackets and many electronic products. On burning, these halogenated compounds forms poisonous gases, which turns into dangerous Hydrochloric acid when comes in contact with water. In areas with limited escape and poor ventilation, the dense black smoke weakens the visibility of people and suffocates their throat, which may lead to loss of lives.
Traditional cables v/s Low smoke cables
Traditional cables are coated with halogen compounds like PVC which is good fire retardant, but if ignited can produce toxic gases and acid. Most of the network cables are coated with chlorine-contained plastic material which is a halogenated compound and will become toxic when exposed to flame.
Low Smoke Halogen Free (LSHF) cables: A harmless substitute
The low smoke halogen free (LSHF or LSZH) cable contains non-halogenated compounds which are still good flame resilient materials and produce very low smoke when burnt. The gas produced with burning of low smoke halogen free material is non-toxic and does not form any type of acid when come in contact with water.
The Low Smoke Zero Halogen (LSZH) cable design incorporates halogen free materials for cable insulation and cable jacket. According to International Electrotechnical Commission (IEC) standards these low smoke cables must pass three tests that are:
These low smoke cables are available in many variants such as:
These LSZH cables are very popular in aircraft, railway and shipbuilding industry where, due to poor ventilation facilities and restricted escape, the protection of people and equipment from poisonous and corrosive gases become very important. These Low smoke cables are highly recommended cables to be installed at public places, airports, and railway stations where human lives and valuable property are uncovered to threat of fire dangers.