Ethernet cable jacket Types - How to choose a flame retardant Ethernet cable

Updated: Jul 23

An Ethernet data cable has an outer sheath protecting the interior wires called a jacket. This jacket can come in many variations designed for different applications.

  • CMP: Communications, Plenum - can be installed in any space

  • CATVP: Cable TV Plenum

  • CL3P: Class 3 Plenum - for in-wall installation in plenum, riser and general spaces

  • CL2P: Class 2 Plenum - for in-wall installation in plenum, riser and general spaces

  • CMR: Communications, Riser

  • CATVR: Cable TV, Riser

  • CL3R: Class 3, Riser - for in-wall installation in riser and non-riser spaces

  • CL2R: Class 2, Riser - for in-wall installation in riser and non-riser spaces

  • CM or CMG: Communications

  • CATV: Cable TV

  • CL3: Class 3 - for in-wall installation in non-riser, non-plenum spaces

  • CL2: Class 2 - for in-wall installation in non-riser, non-plenum spaces

  • CMX: Communications, Outdoor

  • CATVX: Cable TV, Residential

  • CL3X: Class 3, Residential - for in-wall installation in non-riser, non-plenum spaces

  • CL2X: Class 2, Residential - for in-wall installation in non-riser, non-plenum spaces

  • HVAC stands for heating, ventilation, and air conditioning. This term refers to an industry standard for how air is moved inside a building. 

  • Plenum means the spaces usually occupied by the HVAC system, found above and below floors. This empty air space is commonly used for moving air around with or without a dedicated duct.

  • Riser means vertical, typically inside walls and between floors.

  • PVC (Polyvinyl chloride) is the material used in the majority of cable jackets. PVC is simply your typical vinyl.

A network data cable installer is likely to use CM, CMP, CMR, or CMX type jackets.


What Is Cat6 Plenum Cable?

Actually, Cat6 plenum cable is Cat6 CMP cable. The CMP cable (Communications Multipurpose Cable, Plenum) is the most demanding cable in the UL fire protection standard, the safety standard is UL910. This cable is designed to restrict flame propagation to no more than five feet and to limit the amount of smoke emitted during a fire. Therefore, the Cat6 plenum cable is suitable for installation into air plenum spaces. Normally, a Cat6 plenum cable jacket is made up of either a low-smoke polyvinyl chloride (PVC) or a fluorinated ethylene polymer (FEP).


When And Why Do You Need Cat6 Plenum Cables?

The Cat6 plenum cables are designed to provide pathways for return airflows of buildings, facilitating air circulation for heating and air conditioning systems. These Cat6 cables are typically used in the air return pressure boosting system used in ventilation ducts or air handling equipment (above a suspended ceiling or under a raised floor, for example). Since the fir