Plenum rated Cat.5E cable has the same data transmission specifications as regular Cat.5E, but has a jacket that meets specific ANSI requirements for flame retardance and low smoke production. If the building is involved in a fire, the Cat5e Plenum cable will not burn as easy as a standard PVC jacket, and will produce less smoke than a typical Cat5e cable if it does catch fire. It is generally used in public building or HIPPA compliant office environments.
CMR type cables are engineered to prevent the spread of fire from floor to floor and are suitable for vertical shaft applications.CMP: The 'P' in CMP is for Plenum.
CMP cables are suitable for installation in ducts and plenums without the use of conduit. These cables are designed for fire resistance and will generate low smoke and toxin producing characteristics in the event of a fire.CM/CMH/CMG: CM is used for general building wiring such as residential house.
CM cables are used in areas where CMP or CMR is not required.