Typically, there are eight levels of fire resistance for both non-conductive and conductive cables specified by NEC (National Electrical Code). All indoor fiber optic cables must be marked and installed properly for its intended use: plenums, risers and general purpose areas.
(1) A Plenum area is a building space used for air flow or air distribution system (drop ceiling and raised floors).
(2) A Riser area is a floor opening, shaft or duct that runs vertically through one or more floors.
(3) A general purpose area is all other area that is not plenum or riser and on the same floor.
|NEC Code||Description||Cable Application||Possible Substitute|
|OFNP||Optical Fiber Non-conductive Plenum Cable||Plenum, overhead, fiber only||/|
|OFCP||Optical Fiber Conductive Plenum Cable||Plenum, overhead, hybrid (fiber/wire)||/|
|OFNR||Optical Fiber Nonconductive Rise Cable||Riser, backbone, fiber only||OFNP|
|OFCR||Optical Fiber Conductive Rise Cable||Riser, backbone, hybrid||OFCP|
|OFNG||Optical Fiber Nonconductive General-Purpose||General purpose, horizontal||OFNP, OFNR|
|OFCG||Optical Fiber Conductive General-Purpose||General purpose||/|
|OFN||Optical Fiber Nonconductive||General purpose, horizontal, fiber only||OFNP, OFNR|
|OFC||Optical Fiber Conductive||General purpose, horizontal, hybrid||OFCP, OFCR|