When to Use Plenum Rated Cables or Riser Cables

It is very easy to get confused about the cabling requirements for data centers, offices, and other buildings. Most people don’t realize that the National Fire Protection Association or the NFA make regulations on the cables that are needed. They just think that any cable can be installed and it will be okay.

However, if you are a data center owner, office manager, another building owner, or a homeowner, you must make sure the cables you get will meet the National Electrical Code requirements.

As a telecommunication contractor, we can help you to figure out which one of the many cables allowed would be best for your business or home. We know that you want to do what is best when it comes to budgeting, planning, and making sure all regulations are followed. When you work with our telecommunication contractor company, we will send a low voltage cabling contractor to your property.

We will talk to you about the different ratings including CMR cables (communications riser), CMP cables (communications plenum), and the CL/CM cables (general purpose/residential). There are also some other communication cable options that are rated our outdoors.

It is important for our customers to know that these ratings only refer to the jacket on the cable and how fire resistant they are. These ratings have nothing to do with how well data is transmitted through the cables.

Many commercial locations will need to use plenum rated cables or riser cables. If you know that you need to meet the fire regulation codes, keep reading here today to find out more about when to use plenum rated or riser rated cables.

What Does Plenum-Rated Mean?

If you are going to understand why you might need plenum-rated cable, you will first need to know what this material is. A plenum is an additional area used to circulate air for ventilation, air conditioning, and heating. This area is used to send air back to the HVAV system in the building.

Any communications cable must be rated to meet the conditions of the environment – this is the case with plenum rated cables, as well. This is mostly because if there are cables burning, the smoke could go back through the HVAC system and catch the entire building on fire.

What Does Riser-Rated Mean?

Just as with plenum ratings, in order to understand what riser rated means, you will need to know what a communication riser is. A riser is the rooms inside the building that provide a vertical distribution for the communications cables, water supply lines, and electrical conduits.

When it comes to the communications cables, a riser can be a different room on each of the floors. It could also be the room where the electrical gear is stored. Either way, those rooms are not being used for sending air back into the building’s HVAC system. Due to this fact, the fire regulations for the materials used in any of those rooms aren’t as strict as those regulations for plenum areas.

As a telecommunication contractor company, we can help you to figure out whether plenum rated cables or riser cables are best for your building.

What is a Plenum Cable?

You may need to get plenum cables or CMP, due to the National Fire Protection Association regulations. If so, you will be getting cables that use fluorinated ethylene polymer (FEP) or polyvinyl chloride (PVC) in the jacket.

This material is more fire-resistant than the material uses in riser cables. The plenum cables also don’t emit as many toxic fumes when comparing them to different plastic polymers.

If you are putting cables inside a plenum area, it is required that you use plenum cables. Since these cables are more fire-resistant, it is important to understand that they are more costly than other cables.

We also want you to know that you can put plenum cables in a riser space. However, you can’t put riser cables into your plenum spaces.

What is a Riser Cable?

According to the National Electrical Code Requirements, the riser cables are known as CMR. This type of cable does meet the requirements for being fire-resistive. It should be installed in vertical riser areas. It can also be installed in areas that don’t require plenum-rated cables.

One of the times when a riser cable could be used is when the HVAC system has a ducted-return setup. This is because there are separate ducts that are being used to send air back to the HVAC system, instead of the pace over the drop ceiling being used to do this. This type of system helps to stop toxic fumes and smoke from burning cables from going into the HVAC system.

As a telecommunication contractor company, we can help you to determine if your building or home needs riser cables, instead of plenum cables.

Plenum-Rated or Riser-Rated – What Do You Need?

As you can see there are differences between the plenum cables and the riser cables. Different environments require different structured cabling. While cost is a factor for some people, it is also very important to meet the National Fire Protection Association regulations.

You will need to have the proper fire-resistant or fire-resistive cables in your building or home. The more fire-resistant cables (plenum-rated) are the less likely o catch the building or house on fire if they spark or catch fire themselves.

It can be tough to figure out exactly what types of cables you need. There are many different options. However, if you need to have communications cables installed in your building or home, please don’t hesitate to reach out to us. We can have one of our telecommunication contractors help you today!

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