Low-Smoke Zero-Halogen Compounds

https://www.sunualszh.com/products/anti-cracking-lszh-sheath-compound.html

Low-Smoke Zero-Halogen (LSZH or LSOH) refers to a specialized plastic material used in the wire and cable industry for cable insulation and jacketing. It is formulated to release very little smoke and low levels of toxic emissions when exposed to fire.

Most network cables (CAT5, CAT6, etc.) are insulated with materials such as polyvinyl chloride (PVC), polyethylene, or thermoplastic urethane (TPU). When exposed to fire, halogen-based plastics release hydrogen chloride gas, which is highly toxic and turns into hydrochloric acid upon contact with moisture. In contrast, low-smoke zero-halogen (LSZH) cables do not generate this harmful mix of gas, acid, and dense smoke when burned.

Because LSZH materials release no dangerous toxins, they are commonly used in enclosed or poorly ventilated environments such as plenums, aircraft, rail cars, and tunnels—places where smoke accumulation could directly threaten human safety. Their use is increasingly popular and often mandated in situations where the protection of people and equipment is critical. Additionally, LSZH compounds meet the European Union’s Restriction of Hazardous Substances (RoHS) directive as well as comparable North American safety and environmental standards.