What Are OFNP, OFNR, OFNG And OFCG? Understanding Fiber Optic Cable Fire Ratings

Just like copper cables, NEC (National Electrical Code)central strength member which is usually steel. OFCP
requires indoor fiber optic cables be marked with theircables must be properly grounded at both ends. As a
fire and smoking ratings. NEC requires all indoor fiberresult, OFCP cables can not be installed in the same
cables be marked correctly and installed properly forcable tray or conduit as power cables.
its intended use.OFNR Cables:
According to NEC, a building's inside area is dividedOFNR stands for Optical Fiber Nonconductive Riser.
into three types of sections: plenums, risers andOFNR cables are used in Riser areas which are
general purpose areas.building vertical shafts or runs from one floor to
:: What is a Plenum area?another floor. OFNR cables can not be installed in
A Plenum area is a building space used for air flow orplenum areas since they do not have the required
air distribution system. In most buildings, the areafire and smoking rating as Plenum rated cables. OFNP
above a drop ceiling or under a raised floor is used asplenum cables can be used as substitutes for OFNR
the air return (source of air) for the air conditioning.cables.
Those drop ceiling and raised floors are also whereOFCR Cables:
fiber cables are often installed. If those cables wereOFCR stands for Optical Fiber Conductive Riser.
burning, they would give off toxic fumes and theOFCR cables have the same fire rating characteristics
fumes would be fed to the rest of the building byas OFNR cables but they have conducting armor or
the air conditioner. As a result, people could be injuredcentral strength member which is usually steel. OFCR
even though they are a long way from the fire.cables should also be properly grounded at both ends.
:: What is a Riser area?OFCP cables can be used as substitutes for OFCR
A Riser area is a floor opening, shaft or duct thatcables. OFCR cables can not be installed in the same
runs vertically through one or more floorscable trays or conduits as power cables.
:: What is General Purpose area?OFNG Cables:
All other area that is not plenum or riser and on theOFNG stands for Optical Fiber Nonconductive
same floor is a general purpose area.General-Purpose. They are typically used in horizontal
:: Fiber Optic Cable Fire and Smoking Rating Markingscabling, single floor applications. OFNG cables can not
OFNP Cables:be used in plenums or risers. OFNP and OFNR cables
OFNP stands for Optical Fiber Nonconductive Plenum.both can be used as substitutes for OFNG cables.
OFNP cables have fire-resistance and low smokeOFCG Cables:
production characteristics. They can be installed inOFCG stands for Optical Fiber Conductive
ducts, plenums and other spaces used for buildingGeneral-Purpose. They have the same fire
airflow. This is the highest fire rating fiber cable andcharacteristics as OFNG cables but they have
no other cable types can be used as substitutes.conducting armor or central strength members which
OFCP Cables:is typically steel. OFCG cables should be properly
OFCP stands for Optical Fiber Conductive Plenum.grounded at both ends. They should not be installed
OFCP cables have the same fire and smoking ratingin the same cable tray or conduits as power cables.
as OFNP cables but they have a conducting armor or