The cable jacket comprised with different materials based on different applications, In the United States, 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. All materials intended for use on wire and cables to be placed in plenum spaces are designed to meet rigorous fire safety test standards in accordance with NFPA 262 and outlined in NFPA 90A.
The following is the list of cable jacket rating:
OFNP (Optical Fiber, Nonconductive, Plenum)
OFNR (Optical Fiber, Nonconductive, Riser)
OFNP (optical fiber, nonconductive, plenum) are used in plenum applications. They are used inside buildings in plenum areas, the areas between a ceiling and the floor above it, where space is reserved for the circulation of air. They have the highest rated fire retardant where it emits little smoke during combustion. The nonconductive element within OFNP means they contain no electrically conductive components.
OFNR (optical fiber, nonconductive, riser) are used in riser applications. These are spaces inside a building in pathways that pass between floors, such as a vertical zone or space. They are engineered to prevent fire from spreading from floors to floors within buildings.
Here’s a quick summary of the listing requirements for optical fiber cables and raceways,
Types OFNP and OFCP (Plenum): Suitable for use in ducts, plenums and other space used for environmental air.
Types OFNR and OFCR (Riser): Suitable for use in a vertical run in a shaft or from floor to floor.
Types OFNG and OFCG (General-Purpose): Suitable for general-purpose use, with the exception of risers and plenums.
Types OFN and OFC (General-Purpose): Suitable for general-purpose use, with the exception of risers, plenums and other space used for environmental air.
Plenum Optical Fiber Raceway: Have adequate fire-resistant and low smoke-producing characteristics.
Riser Optical Fiber Raceway: Have fire-resistant characteristics capable of preventing the carrying of fire from floor to floor.
General-Purpose Optical Fiber Cable Raceway: Resistant to the spread of fire.
SOURCE: http://www.tarluz.com/fiber-optic-network/know-difference-among-lszh-ofnr-ofnp-fiber-optic-cabling/