Increasingly used in public and government buildings and where there is sensitive electronic equipment (i.e. Hospitals, Supermarkets, Airports, Control Rooms & Computer Suites) these cables are designed for increased safety in the case of a fire:

Historically, most cables used in installations have been insulated with PVC or similar materials.  In fires, these insulation materials release chlorine gas.  Chlorine is a poisonous gas and a danger to people.  In addition it forms hydrochloric acid when coming into contact with water.   Hydrochloric acid can have devastating effects on adjacent equipment.

To overcome the problems associated with the release of chlorine gas, halogen-free cables are used.  Typically a halogen free cable is made of polypropylene, which does not produce a dangerous gas or acid in fire conditions.

In the event of a fire, both types will emit very low levels of smoke. LSF cable will emit toxic gases while LSZH will limit the emission of these (typically under 0.5% hydrogen chloride emission). In addition to being toxic, hydrogen chloride is corrosive to equipment. The use of LSZH cables protect both people and limit the amount of equipment damage during a fire situation.

LSF is often a modified PCV with hydrogen chloride additives and while performing better than PVC will give off more smoke and fumes than LSZH. Hydrogen chloride emissions of LSF cable may reach up to 18%.

Compared with normal PVC cables and LSF, zero halogen cables have better fire retardant properties, low toxic and corrosive gas emissions and low smoke emission.