Indoor optical fiber cable outer sheath material

Indoor fiber optic cables are an essential component of modern telecommunications infrastructure, providing fast and reliable data transmission within buildings and other indoor environments. One important consideration when selecting indoor fiber optic cables is the outer sheath material and its fire prevention level. In this article, we will discuss the different types of outer sheath materials used in indoor fiber optic cables and the fire prevention levels associated with each type.

Types of Outer Sheath Materials

The outer sheath material of an indoor fiber optic cable is the protective layer that surrounds the cable and provides mechanical protection and environmental resistance. The most common types of outer sheath materials used in indoor fiber optic cables are:

PVC

Polyvinyl chloride (PVC) is a commonly used outer sheath material for indoor fiber optic cables. PVC is a low-cost material that provides good mechanical protection and resistance to environmental hazards such as moisture and UV radiation. However, PVC has poor flame-retardant properties and is not recommended for use in areas with high fire risk.

LSZH

Low smoke zero halogen (LSZH) is an outer sheath material that is becoming increasingly popular for indoor fiber optic cables. LSZH is a thermoplastic compound that contains no halogen and produces low smoke and toxic gas emissions when exposed to fire. LSZH provides good mechanical protection and environmental resistance, and is ideal for use in areas with high fire risk such as data centers, hospitals, and public buildings.

Plenum

Plenum is an outer sheath material that is specifically designed for use in air handling spaces such as ducts, plenums, and other enclosed areas. Plenum is typically made from a fluoropolymer material such as FEP (fluorinated ethylene propylene) or PTFE (polytetrafluoroethylene). Plenum provides good mechanical protection and environmental resistance, and has excellent flame-retardant properties. Plenum is required by building codes and regulations in many jurisdictions for use in air handling spaces.

Armored

Armored fiber optic cables have an additional layer of armor, typically made from steel or aluminum, that provides enhanced mechanical protection and resistance to external hazards. Armored cables are often used in harsh indoor environments such as factories, warehouses, and other industrial settings where the cable is subject to mechanical damage. Armored cables are available with a variety of outer sheath materials including PVC, LSZH, and plenum.

Fire Prevention Levels

The fire prevention level of an indoor fiber optic cable refers to its ability to resist ignition and flame spread in the event of a fire. Fire prevention levels are determined by a series of tests that evaluate the cable's performance in the presence of heat and flame. The most common fire prevention levels used for indoor fiber optic cables are:

Non-Plenum (CMP)

Non-plenum cables are not suitable for use in air handling spaces and are typically used in non-critical applications such as residential buildings and small offices. Non-plenum cables are required to meet the UL-910 test standard, which evaluates their ability to resist ignition and flame spread.

Plenum (CMP)

Plenum cables are required by building codes and regulations in many jurisdictions for use in air handling spaces. Plenum cables are required to meet the UL-910 and NFPA-262 test standards, which evaluate their ability to resist ignition and flame spread in air handling spaces.

Low-Smoke Zero Halogen (LSZH) (CMX)

LSZH cables are becoming increasingly popular for use in indoor fiber optic applications due to their low smoke and toxic gas emissions in the event of a fire. LSZH cables are required to meet the IEC 60332-1-2 and IEC 61034 test standards, which evaluate their ability to resist flame spread and produce low