THE TERM "HALOGEN FREE"

During a fire incident the most dangerous toxic gases emitted are acid gases such as hydrogen chloride (HCI), hydrogen fluoride (HF) and hydrogen bromide (HBr).

These gases occur during combustion of materials containing halogen materials: Chlorine, Fluorine, Bromine, Iodine and Astatine.

Consequently, insulation materials of cables should not contain halogen materials in response to the security requirements.

On the other hand, halogen free materials such as polyethylene or polypropylene present an adverse reaction to fire : they spread flame and fire. To solve this problem, it is possible to add halogen materials to increase the flame retardant effect of the insulation. Other insulation materials are halogen free but emit toxic substances when affected by fire.