Optical fiber, nonconductive, riser (OFNR) is a type of optical fiber cable.As designated by the National Fire Protection Association (NFPA), this name is used for interior fiber-optic cables which contain no electrically conductive components, and which are certified for use in riser applications; they are engineered to prevent the spread of fire from floor to floor in a building. Typically they are tested for compliance with ANSI/UL 1666–1997, Standard Test for Flame Propagation Height of Electrical and Optical-Fiber Cable Installed Vertically in Shafts. NFPA NEC 2005 Art 770.51(B) FPN.
They are distinct from optical fiber, nonconductive, plenum cable (OFNP), and general-purpose optical cable.
Underwriters Laboratories defines the following related abbreviations http://www.ul.com/global/eng/pages/solutions/standards/accessstandards/catalogofstandards/standard/?id=1651_3: