Have You Chosen the Right Cable Jackets?

Have you noticed that patch cables are all wrapped in various jackets? These cable jackets are important to serve as the protection for inner cable parts. Different kinds of jackets can influence the applications as well. Knowing the differences in cable jackets will help you make better decisions when choosing cables. Lots of materials can be made as cable jackets to cope with different situations. This article will mainly introduce some common types and analyze their distinctions.



PVC (polyvinyl chloride) is a common jacket type widely used for general patch cables. The low cost and easy manufacture contribute to its popularity around the world. You can find PVC jackets almost everywhere when patch cables are used. PVC material is highly moisture-resistant so that can be perfectly applied to humid environment. But it also has some defects that will limit the service lifespan. For example, PVC material often becomes fragile under direct sunlight and its flexibility is restricted when greater bending is required.


LSZH (low smoke zero halogen) is the material that gives off low toxic and corrosive gas under fire. It greatly ensures the high visibility and low respiratory damage when cables come across open fire or short circuit fault. LSZH cable jacket is typically applied to areas where smoke factor is considered to be the most important, such as aircraft, rail cars, ships, buildings and so on.


OFNP (optical fiber nonconductive plenum) is specified by NFPA (National Fire Protection Association), which has no electrically conductive component inside optical cables. This type of cable jacket can effectively prevent fire and emit low smoke. OFNP cable is the highest fire rating fiber cable and has no replacement. Places including ducts, plenums, and other building airflow areas are suitable for installation.


PUR (polyurethane) cable jacket is the thermoplastic material that is usually used in harsh environment. It provides both mechanical resistance and chemical resistance. Thus, PUR cable can be installed for industrial applications where strong protective coating is demanded. Also, its flexibility makes itself a good material for retractile patch cables in continuously flexing applications. But it is more expensive than the common cable jackets.


PTFE (polytetrafluoroethylene) sheath is a synthetic fluoropolymer material suitable for extreme environment. It is very durable under both high and low temperatures and can not be affected by most oils, fuels and fluids. This kind of cable jacket is widely used in military, aerospace, coaxial, and appliance wiring applications.


Rubber jacket is a good option for portable power applications in outdoor or wet environment. It has better performance than plastic materials in flexibility, high temperature resistance and durability. Other applications like mining submersible pumps, control circuits, motor and associated machinery, construction equipment, etc. are also available.


Silicone is the synthetic rubber with greater flexibility and stronger resistance against extreme temperatures and chemicals. Of course, it does not operate as high temperatures as PTFE. But with the extremely supple characteristic, silicone cable sheath is perfect for applications where lots of wire bending are required. And when it encounters fire, only a small amount of smoke will be produced which is also environmental-friendly.


After reading this article, you may get a general idea about the current cable jacket types and where they should be used. And certainly, if you want to find the most suitable jacket for your project, knowing this information is not far enough. But I hope this article can let you understand the importance of choosing a right cable jacket in your future applications.

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Fiber Resistant LS0H Cables

With the increased demand for safety in public areas and buildings, contractors are now being advised to install materials thar are zero halogen cables to peoples in case of fire. It is now understood that smoke and poisonous fumes can be a greater risk to lives than that of fire alone.

What is Resistance to Fire?
Resistance to fire is the property of a material of assembly to withstand fire or give protection from it and it is measured as the time a product can mantain a level of functionality during a fire.

Fire resistance may be built-in both structurally and by the correct choice and application of building materials. The resistance-to-fire (of a cable) is the term used to describe how long a cable continues to operate in a fire. This may be of primary concern, for instance, in life safety of fire fighting installations.Cable resistance to fiber concerns: the ability of a cable to maintain functionality during fire; the duration of survival in working condition.

To be assured you are buying a cable that will offer security during fire, it must pass 3 tests pertaining to halogen content, low smoke density and flame propagation. The resistance-to-fire performance of cable is indicated in term of survival time which are 15, 30, 60, 90 and 120 minutes of operation in a standardized fire condition at European Level and equipment international (IEC). Local standards and customers specs include their own requirements witch are achieved as well by FiberStore local or tailor-made products.

Fiber-retartant, low smoke halogen free cable (LSZH) and wire has been commercially available fro shipboard applications since the 1970S, offshore marine platforms, rapid transit and similar applications where people are present in confined areas. When worked with other fiber prevention and suppression practices, fire-retardant LSZH cables can help minimize fire-rated deaths and property damage. However, gases produced by all burning materials – whether LSZH or not – are extremely toxic.

Advantages and Disadvantages of LS0H cables

Pro: LSZH wire and cable produces less smoke when burned, which permits people to exit a burning building more quickly and results in less damage.

Con: Because LSZH is more susceptible to jacket cracking caused by pulling lubricants or cable bending, special lubricants has been developed to minimize cable damage during installation.

Pro: Because LSZH releases little or no halogen gas when burned, it reduced the damages to the human respiratory system if inhaled and contributes to less corrosion damage to equipment near the fire.

Cons: LSZH jacket compounds usually have very high filler content to provide the required flame and smoke performance. As a result, most have poorer mechanical, chemical resistance, water absorption and electrical properties than non-LSZH compounds.

Pro: LSZH jackets have a lower coefficient of friction than some non-LSZH jackets, which can make installatin easier.

Cons: The current generation of LSZH cables has not yet established a proven history of long-term performance.

What Should You Know about Low-Smoke Zero Halogen Cables

Halogen is a nonmetallic elements such as fluorine, chlorine, iodine or bromine. It is generally used as flame inhibitors in many plastics, including PVC that goes into cable insulation and electronic products. Halogens are a group of chemical elements including iodine, bromine, fluorine, astatine, and chlorine. When these elements are exposed to fire, they form hazardous gases which are harmful to harm the eyes, nose, lungs, and throat.

LSZH is a material category used to classify cable insulation. LSZH (Low Smoke Zero Halogen) cable insulation is made of materials designed to give of reduced smoke and no halogen when exposed to fire. When combined with other fire deterrents and control practices, Zero Halogen Cables can help reduce fire related casualties and property destruction. These cables will also don’t give off hazardous gas/acids or toxic smoke when exposed to fire.

LSZH cables decrease the extent of smoke produced through fire and is normally used in inadequately ventilated areas, for instance, airplane and some areas that people may be affected by smoke and toxic fumes.

Beside the halogen free features, LSZH cable also has lighter weight, this is convenient especially if the cables are run overhead in a dropped ceiling. At the same time, the impact of halogen free cables will also be lower if there is a fire because there are fewer toxic chemicals involved.

Many different Fiber Optic Cable suppliers are now making low-smoke, zero-halogen cables. And it is currently widely used in Europe and elsewhere in the world contains halogens. The European market is demanding that cables used in LANs. WANs, etc. Meet LSZH specification. The IEC 60332-1 governs the Flame Retardant Grade specifications in reference to LSZH cable.

Essentially the compound used in manufacturing cables meeting the above specifications reduces the amount of dangerous/poisonous gases in case of fire. The main difference in specifications between IEC 60332-1 versus UL 5181, UL 1666 and UL 910 is that the cable under the IEC specifications continue to burn while still emitting very low gases. UL specs demand that the flame be extinguished, but it can still be emit poisonous/dangerous gases.

Most safety advocates are calling for the used of LSZH cables, especially for the plenum space. Review your local building codes to determine if you must use LSZH cable. Non-LSZH cables will produce corrosive acids if they are exposed to water when burned; such acids may theoretically further endanger equipment.