The plenum (pronounced PLEH-nuhm) is hidden space within a building,
which is used for Heating, Ventilation, and Air Conditioning (HVAC), and
can be used to run cables. Plenum space is normally above a suspended ceiling
or under a raised floor. Plenum cable is a particular qualification of
wire that has been fire code rated and approved
to be run through plenum spaces.
Plenum cable must meet two requirements to meet most fire codes:
- Plenum cable must not burn easily
- Plenum cable must not emit toxic fumes when exposed to extreme heat
In the US, plastics used in the construction of plenum cable are regulated
under the National Fire Protection Association standard NFPA 90A: Standard
for the Installation of Air Conditioning and Ventilating Systems. Plenum
cable is jacketed with a fire-retardant plastic jacket of either a low-smoke
polyvinyl chloride (PVC) or a fluorinated ethylene polymer (FEP). Because
of these requirements, plenum cable is more expensive than non-plenum cable.
Plenum cable is also less flexible and more difficult to work with than
regular network cable.
Cables designated to be run between floors in non-plenum areas, including
isolated conduits and drywall, is classified as
riser cable. The fire requirements on riser cable are not as strict.
Thus, plenum cable can always be used in place of riser cable, but riser
cable cannot replace plenum cable in plenum spaces.
ORDERING PLENUM CABLES:
Plenum rated cables can be special ordered for a limited number of our
products. Additional production time and minimum orders may apply;
check with a DataPro customer service person for specifics details.
Please contact us for more information.