A Guide to Cable Jackets: Find the Perfect Fit for Every Installation

Posted on Jun 14, 2024 by

You are planning to purchase some network cables for your new Ethernet setup or home theater to run through, and you already know exactly the category of network cables and the lengths you need. So, you head to the first page of a site or go offline to buy. However, you encounter a new problem: how to choose the right type of cable jacket? PVC, PE, or LSZH? If you are not clear about the differences and pros and cons of these cable jackets, you might end up buying cables that are unsuitable for your needs or waste valuable time deciding which type to choose.

What Types of Cable Jackets Options Does FS Offer?

FS can provide customers with a whole range of cables for all purposes with different cable jackets, and these network cable products are all available for immediate delivery. The differences in cable jacket types determine their suitability for different scenarios. To choose the most suitable cables for your application, let's first understand these three types of cable jackets that FS provides.

PVC Cable Jacket: The Most Widely Used Cable Jacket Type

What is PVC?

PVC stands for Polyvinyl Chloride, a widely used plastic material. PVC is chosen for its durability, cost-effectiveness, and ease of processing. It has excellent electrical insulating properties and provides adequate protection against physical damage and environmental factors.

PVC Cable Jacket

The features of PVC cable jackets that make them widely used typically include:

  • Superior Mechanical Performance: PVC offers high tensile strength, bending strength, and impact resistance, as well as good abrasion and weather resistance.

  • Excellent Chemical Stability: PVC cable jacket resists most organic solvents, acids, and bases. It remains stable in environments with pH values ranging from 0 to 14. This characteristic enables PVC cables to perform well in chemically harsh environments, such as sewage treatment plants and chemical laboratories, significantly broadening their applications.

  • Low Cost: The mature production process and abundant raw material supply for PVC result in relatively low costs. This makes PVC-jacketed cables competitively priced, meeting the demands of the mass market.

When to Use PVC Jacketed Cables?

While PVC is low-cost and flexible, it has potential drawbacks. During a fire, this material can release dense smoke and hazardous gases, such as hydrogen chloride.

This issue can be particularly severe if toxic smoke and gases are released in areas that can quickly spread to other parts of a building. Thus, the National Electrical Code (NEC) categorizes PVC cable jackets into three groups according to their fire rating levels: CM, CMR, and CMP. These levels indicate where the cables can be installed to ensure contractors and homeowners use the appropriate outer jacket type for the installation area.

The network cables with PVC outer jackets provided by FS have all passed the UL standards and comply with the fire ratings specified by the NEC. Below is a detailed introduction to these three different fire ratings. You can choose the correct fire rating based on the actual application scenario of your network cables:

Category Fire Rating Description Applications
PVC CM Communications Multipurpose Cables marked with CM are mainly used for Ethernet and communication applications. They have passed the "vertical tray flame test," meaning they typically do not propagate flames beyond eight feet. Ideal for home use; they can be installed in walls or ceilings without additional fire protection measures.
PVC CMR Communications Multipurpose Riser Cables marked with CMR are for buildings with multiple stories. They prevent fires from spreading between floors and are more resistant to fire than the CM cable. Suitable for multi-story buildings where cables must run vertically between floors; they cannot be used in air ducts.
PVC CMP Communications Multipurpose Plenum Cables marked with CMR are designed for "plenum" areas in buildings; They restrict the spread of fire, do not emit toxic fumes when burning and will not combust. Ideal for large commercial buildings, hospitals, and schools; they can also be used where CM and CMR cables are applicable.

CM/CMR/CMP Cable Application

PE Cable Jacket: Protects Network Cable From Harsh Environments

What is PE?

PE stands for Polyethylene, a durable and waterproof plastic material commonly used for outdoor cable jackets. PE cable jackets can withstand harsh weather conditions and UV radiation.

When to Use PE Jacketed Cables?

PE has excellent moisture and weather resistance, good electrical properties over a wide temperature range, and is abrasion-resistant. Thus, PE is the standard jacket material for outdoor network cables. FS's outdoor bulk Ethernet cables are made of this material, which enables them to withstand harsh outdoor environments effectively. Moreover, they can be directly buried underground without the need for conduit.

Direct Burial Cable Application

However, one drawback of PE cable jackets is that they do not self-extinguish when burned. When heated to their melting point, they may soften and drip. If the dripping falls onto other combustible objects, it could cause a larger fire. Therefore, using network cables with PE jackets in places sensitive to fire risks is not recommended.

LSZH Cable Jacket: Provides the Highest Level of Safety in the Event of Fire

What is LSZH?

LSZH stands for "Low Smoke Zero Halogen," describing two specific properties of this jacket material. "Low smoke" refers to the reduced amount of smoke produced when the material burns, and "zero halogen" indicates that no halogenated compounds are used in manufacture.

LSZH Cable

Currently, cables with LSZH jackets are primarily used in Europe. Under the framework of the Construction Products Regulation (CPR) in 2011, Europe has created new cable fire protection classes, requiring a reassessment of building fire safety. If you are planning to purchase cables with LSZH jackets, you may need the following four different fire resistance classes:

  • Bca: This means that cables with this type of jacket have the highest fire resistance performance and are mainly suitable for bedroom environments, prisons, hotels, accommodation buildings larger than 500 square meters, conference venues, etc.

  • Cca: This class is commonly used for LSZH cables and is suitable for non-bedroom environments such as factories, offices, classrooms, sports venues, shopping areas, etc.

  • Dca: If cables are used in bundles for applications related to personal safety, they must meet the Dca fire resistance class.

  • Eca: Unlike the other three fire resistance classes tested according to the EN 50399 standard, Eca is tested according to the EN 60332-1-2 standard and represents the basic requirement for fire resistance. Cables cannot be installed in bundles.

FS currently offers Cat6 and Cat6a network patch cables with LSZH jackets. FS network cables have obtained B2ca, Dca, Eca, and Fca certifications. We can provide a Declaration of Conformity/Performance that states the cables' Euroclass grading, and we add the CE marking to each product.

When to Use LSZH Jacketed Cables?

In fire incidents, the primary danger is not the fire itself but the smoke and gases produced during combustion. When LSZH cables burn, they do not produce toxic gases and emit very little acidic gas, which can reduce harm to personnel and equipment. Furthermore, LSZH cables are less likely to catch fire during an incident and can help prevent the spread of flames and the escalation of the disaster. Therefore, cables with LSZH jackets are typically required in high-safety environments, such as airports, military bases, commercial centers, and other densely populated areas. However, while LSZH offers the best safety, its cost is the highest. The large-scale application of LSZH cables may pose a challenge for individuals or small businesses with limited funds.

FAQs About Cable Jackets of FS Cables

Q1: How do I know if I need CMP?
A: CMP jackets are made from low-smoke PVC, or fluorinated ethylene polymer (FEP), so CMP cable burns clean, meaning it does not give off toxic fumes and can self-extinguish. On the other hand, PVC releases thick, poisonous smoke when burned. If your cabling needs to pass through air circulation spaces, such as the gaps between drop ceilings and floors, you need CMP cables to meet fire safety requirements.
Q2: Is LSZH the same as Plenum?
A: Low-smoke zero-halogen is not the same as a plenum. LSZH cables are free from halogenic elements (fluorine, chlorine, bromine, iodine, and astatine), which are very common in PVC material but are toxic when burned.
Q3: What is the difference between outdoor and direct burial outer jackets?
A: Regarding jackets, outdoor and direct burial are similar, but the direct burial cables are filled with gel to prevent water from leaking into the cable.
Q4: Can CMP cables be used in riser places suitable for CMR cables, and vice versa?
A: Due to their high fire resistance rating and low smoke emission characteristics, CMP cables can be used in CMR scenarios. However, they are not recommended for use in CMP scenarios, as they may not meet the strict requirements for smoke and toxic gas emissions in air circulation environments.
Q5: Do cable jacket materials affect cable performance?
A: The cable jacket's material mainly affects the cable's durability and safety, not the network performance itself. However, using unsuitable jacket material in a harsh environment can damage the cable, thus impacting network performance.


FS offers a range of high-quality cable jackets to meet various application needs. Whether you need economical PVC cables, durable PE outdoor cables, or the safest LSZH cables, FS has the right product for you. By choosing FS cables, you get high-quality, reliable, and safety-compliant products that ensure smooth and stable network installation and long-term performance.

You might be interested in

See profile for Sheldon.
Decoding OLT, ONU, ONT, and ODN in PON Network
Mar 14, 2023
See profile for Irving.
What's the Difference? Hub vs Switch vs Router
Dec 17, 2021
See profile for Sheldon.
What Is SFP Port of Gigabit Switch?
Jan 6, 2023
See profile for Migelle.
PoE vs PoE+ vs PoE++ Switch: How to Choose?
May 30, 2024
See profile for Moris.
How Much Do You Know About Power Cord Types?
Sep 29, 2021