Low Smoke Zero Halogen Cable refers to the sheathing material in the cable and insulation in wires. The HFFR/LSFR are made of a thermoplastic compound which emits limited smoke, no halogen as compared to normal cables. Besides, it will not produce any poisonous gases when exposed to fire.
In the event of a fire in a building, there is a danger of electric cables burning behind the wall for a long period of time. It then spreads from room to room emitting toxic gases and smoke. In such a scenario, getting out of the building becomes difficult. First of all, while the PVC cable is getting burned, it fill the rooms with thick black smoke which makes it almost impossible to find a way to the exit. In addition to smoke, poisonous halogen gases are also generated from burning PVC cables. This causes the occupants to lose consciousness and die even before the fire touches the body
In such a situation, HFFR/LSFR cables are desirable because it reduces the amount of smoke and poisonous gases generated, which significantly improves the chance of safe escape for the inhabitants. Also, it makes firefighting operations easier as the firefighters can easily identify and reach the source of the fire.
Aluminum Hydroxide/ATH is the most widely used flame retardant filler in HFFR/LSFR cables. About how aluminum hydroxide works, please read the following article: