If protection of equipment or people is a design requirement, consider low-smoke zero-halogen (LSZH) jacketed cables. They emit fewer toxic fumes than standard PVC-based cable jackets. Typically, LSZH cables is used in confined spaces such as mining operations where ventilation is of concern.
The function and technique parameter of LSZH fiber optic cable is just like common fiber optic cables, and inner structure is also similar, the basic difference is the jackets. LSZH fiber optic jackets is more fire-resistant compared with common PVC jacketed cables, even when they are caught in fire, the burned LSZH cables provide low smoke and no halogen substances, this feature is not only environment protective but the low smoke when it got burned is also important to people and facilities in the fired place.
LSZH jacket is made up of some very special materials which are non-halogenated and flame retardant. LSZH cable jacketing is composed of thermoplastic or thermoset compounds that emit limited smoke and no halogen when exposed to high sources of heat. LSZH cable reduces the amount of harmful toxic and corrosive gas emitted during combustion. This type of material is typically used in poorly ventilated areas such as aircraft or rail cars. LSZH jackets are also safer than Plenum-rated cable jackets which have low flammability but still release toxic and caustic fumes when they are burned.
Low smoke zero halogen is becoming very popular and, in some cases, a requirement where the protection of people and equipment from toxic and corrosive gas is critical. This type of cable is ever involved in a fire very little smoke is produced making this cable an excellent choice for confined places such as ships, submarines, aircraft, high-end server rooms and network centers.
Every coin has two sides. Since LSZH cables have so many benefits listed above, what are the Cons of the cable?
1. LSZH is more susceptible to jacket cracking. Special lubricants have been made to minimize damage during installation.
2. LSZH jacket has a high filler content, around 50% to provide the required flame and smoke performance. This results in a lower mechanical, chemical resistance, water absorption and electrical properties then non LSZH compounds.
3. The current generation of LSZH cables has not yet established a proven history of long time performance.
The LSZH cables are available with 1, 2, 12, 24 fibers, and variable sub-cable dimensions that support specific termination and routing requirements. They are suitable for halogen free and many international installations. LSZH cable contains no flooding gel and is OFNR Riser rated, is perfect for installation in conduits between buildings and run directly thru risers to a convenient network or dome fiber optic splice closure without a separate point of splice at building entrance.
There are also LSZH fiber optic patch cords available. Both LSZH fiber optic cables and LSZH fiber optic patch cords are required for the Rosh compliant cable assemblies, but Rosh standard is more strict besides it require the cables to be LSZH type. LSZH fiber optic patch cable are used widely used in the places where expensive equipment would be damaged if exposed to corrosive gases, and they are also used in crowded areas like commercial centers and sports centers.