Ethernet Jacket Types: A Comprehensive Guide
Ethernet cables are crucial for network performance, but what many people overlook is the protective jacket around the cable. The jacket type determines the environment the cable is suited for, its durability, and its safety features. Whether you're installing cables in an office, a data centre, or outdoors, choosing the right jacket is essential for performance and compliance with safety regulations.
Below is a detailed look at the most common Ethernet cable jackets and where each is best applied.
PVC (Polyvinyl Chloride) Jackets
Polyvinyl Chloride (PVC) jackets are among the most common Ethernet cable types, used widely for indoor applications. PVC is a versatile and affordable material that provides the necessary flexibility and protection for day-to-day networking needs in homes and offices. The material is light, easy to install, and widely available. However, it does have some limitations in terms of environmental resistance.
PVC jackets are not designed to withstand UV exposure or extreme temperatures, making them unsuitable for outdoor or high-heat environments. Another significant downside is that PVC releases toxic fumes when it burns. This means in the event of a fire, cables with PVC jackets could contribute to hazardous conditions by producing dense, toxic smoke. As a result, building codes often restrict its use in public and densely populated spaces.
LSZH (Low Smoke Zero Halogen) Jackets
Low Smoke Zero Halogen (LSZH) jackets are made from compounds that do not emit halogens (toxic gases such as chlorine or fluorine) when burned. Moreover, these jackets produce far less smoke compared to PVC, making them ideal for environments where safety is a primary concern. LSZH cables are especially important in public buildings, tunnels, and confined spaces where fire safety regulations are stringent, and the presence of people means that reducing the potential for toxic smoke is critical.
For these reasons, LSZH cables are commonly used in airports, hospitals, and data centres—environments where human safety is paramount. The trade-off for these safety features is a higher cost compared to PVC cables, as well as a slightly stiffer jacket, which may require more careful handling during installation.
Plenum Jackets
Plenum-rated Ethernet cables are specifically designed for spaces where air circulates, such as heating and air-conditioning ducts. The term "plenum" refers to these air spaces within buildings. In case of a fire, the open-air circulation in plenum spaces can quickly spread flames and toxic fumes, which is why building codes strictly regulate the type of materials allowed in these spaces.
Cables with plenum jackets are made from special flame-retardant materials designed to withstand higher temperatures and prevent the spread of fire. These materials also emit significantly lower levels of smoke and toxic gases when exposed to heat. Due to these stringent requirements, plenum-rated cables are typically more expensive than standard PVC or even LSZH cables. However, they are mandatory for installations in plenum spaces, making them the only viable choice for HVAC systems, drop ceilings, and raised floors.
Riser Jackets
Riser-rated Ethernet cables are another classification defined by building codes, though these cables are intended for use in vertical spaces within buildings—such as between floors in a riser shaft or elevator shaft. Riser-rated cables are flame-retardant, but they are not required to meet the same strict fire resistance standards as plenum cables.
Typically used for in-wall installations or connecting networking equipment between floors, riser-rated cables provide adequate protection against fire spread in these vertical spaces. They are generally more affordable than plenum cables but may not be suitable for use in ducts or air-handling areas. While riser cables are safer than standard PVC, they should not be substituted for plenum-rated cables in air-circulating spaces.
Outdoor / UV-Resistant Jackets
When Ethernet cables need to be installed outdoors, they require a jacket that can withstand the elements. Outdoor-rated Ethernet cables feature jackets made from UV-resistant and weatherproof materials, making them suitable for exposure to direct sunlight, rain, and varying temperature extremes. These cables are robust and designed to handle the harsh conditions of outdoor environments over time without deteriorating.
Outdoor-rated cables are ideal for connecting buildings, outdoor security systems, or any installation that requires external exposure. Unlike PVC or riser cables, outdoor cables can also be buried directly underground without additional conduit. However, because they are thicker and tougher, they are less flexible and harder to install in tight spaces.
Gel-Filled / Water-Resistant Jackets
For installations in wet or damp conditions, such as underground or in locations prone to water ingress, gel-filled Ethernet cables are the best choice. These cables contain a protective gel inside the jacket, which acts as a barrier to moisture and prevents water from reaching the internal wiring.
The gel filling provides long-lasting protection and ensures that the cable continues to perform even in challenging environments. These cables are commonly used for direct burial, underwater applications, or in areas prone to flooding. However, their unique construction also makes them heavier and more challenging to handle during installation, as the gel can make splicing and termination messier.
Understanding the Differences: When to Use Each Type
Selecting the right Ethernet cable jacket depends on the installation environment and specific requirements. For basic indoor setups in homes and offices, PVC cables suffice. However, in environments where fire safety is a concern, LSZH or plenum cables should be used. Riser cables are suitable for vertical runs within buildings, while outdoor-rated and gel-filled cables are designed to withstand exposure to weather and moisture.
Understanding these different jacket types allows for informed decisions about both safety and functionality, ensuring your networking infrastructure is not only efficient but also compliant with local building codes and safety regulations.
Comparison Table
| Jacket Type | Primary Use | Pros | Cons |
|---|---|---|---|
| PVC | Indoor | Inexpensive, flexible | Not fire or UV-resistant |
| LSZH | Indoor, fire-sensitive | Low toxicity, minimal smoke | More expensive |
| Plenum | Air ducts, plenum spaces | Highly fire-resistant | High cost |
| Riser | Vertical installations | Flame retardant, affordable | Not suitable for plenum spaces |
| Outdoor/UV Resistant | External environments | Durable, UV and weather-resistant | Heavy, less flexible |
| Gel-Filled/Water-Resistant | Underground, wet areas | Superior moisture protection | Cumbersome to install |