What Is Plenum Cable?


Welcome! If you're dealing with cabling in building spaces, especially areas that involve air circulation, you've got to know about plenum cables. This guide will arm you with all the essential information.

What is a Plenum Space?

A plenum space is an area within a building where air circulates as part of heating, ventilation, or air-conditioning (HVAC) systems. Think of spaces above drop ceilings or below raised floors. The key point? Cables in these areas must meet stringent safety requirements.

What is Plenum Cable?

Plenum cable is specially designed for use in plenum spaces. Unlike regular cables, plenum cables are made with materials that are fire-resistant and produce low amounts of smoke when burned. This is crucial for minimizing fire hazards and toxic fumes.

Benefits of Using Plenum Cable

  • Fire Safety: In case of a fire, plenum cables are designed to not catch fire easily and to minimize smoke, which is vital for evacuation and firefighting efforts.
  • Reduced Toxicity: The materials in plenum cables emit lower levels of toxic fumes compared to traditional cables. That’s a win for both safety and air quality!
  • Code Compliance: Using plenum cables in required spaces ensures you're complying with building codes, making your life simpler when inspections roll around.

When Should You Use Plenum Cable?

Plenum cables are essential in any space that serves as an air-handling compartment. This includes commercial buildings like offices, schools, and hospitals. If you're unsure, consulting building codes or a professional is a smart move.

Plenum Cable vs. Riser Cable vs. PVC Cable

  • Plenum Cable: Fire-resistant and low-smoke. Use in plenum spaces.
  • Riser Cable: Fire-resistant. Use in vertical shafts and from floor to floor.

How to Identify Plenum Cable

Look for cable markings like "CMP” when purchasing. These markings are your assurance that the cable is suitable for plenum spaces. With that said it's important to only purchase plenum cable with safety certification. Nor should you purchase plenum cable with copper clad aluminum. CCA with a plenum cable is not an approved plenum cable type. It will not pass certification.

Plenum Cable Markings

For example our plenum cable jacket will show as:  C(UL)US CMP -- ETL Verified

These markings ensure regulatory testing by laboratories for safety and plenum compliance.

With the in flux of cabling brands in the recent years we ask you to take extra precaution when shopping low priced plenum cabling. Feel free to reach out to use with any specific questions for this topic.

Applications of Plenum Cable

You'll typically find plenum cables in areas where a lot of people gather or where air circulates freely, such as schools, hospitals, and office buildings. They're commonly used for data, voice, and video signaling.

Regulatory Guidelines

The National Electrical Code (NEC) in the U.S. sets the standards for plenum, riser, and general-use cables. Make sure to check local guidelines if you're in a different country.


So there you have it—the A to Z on plenum cables. Whether you're a contractor, building manager, or just a curious soul, knowing when and why to use plenum cable can make a significant difference in safety and compliance.

And that's a wrap! Hope you found this guide useful. Stay safe and make informed choices!

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