OFNR: Abbreviation for optical fiber, nonconductive, riser . Note: OFNR is the designation given by the National Fire Protection Association (NFPA) to interior fiber-optic cables which contain no electrically conductive component, and which are certified for use in riser applications. [After FAA]
OFNR - Riser type cables passing the UL 1666 test are engineered to prevent the spread of fire from floor to floor and are suitable for vertical shaft applications.