Definition of Plenum Cabling in the Network Encyclopedia.

What is Plenum Cabling (in Computer Networking)?

Plenum Cabling, also known as CMP cabling, is a grade of cabling that is resistant to combustion and is used for horizontal cable runs in building plenums and vertical rises such as elevator shafts. A plenum is a horizontal space within a building that houses building components and allows the movement of air.

False ceilings are not considered plenums. Plenum cabling is less flexible and costlier than polyvinyl chloride (PVC) cabling. The external insulating jacket of plenum cabling is usually a fluoropolymer such as Teflon FEP.

Plenum cables use treated jackets, usually low-smoke PVC (polyvinyl chloride) or FEP (fluorinated ethylene polymer). The jacket is designed to 1) hinder the progression of flame and 2) not release the harmful smoke that normally accompanies any type of burning plastic. We use Teflon (or PTFE) coated wires in our plenum network cables to make sure that the cables are safe and heat-resistant.

Plenum cables are the highest standard and can safely be substituted for any other cable type such as riser, CM, CL2 or CL3 cables.