Optical fiber cables are not required to be listed and marked where the length of the cable within the building, measured from its point of entrance, does not exceed _____ and the cable enters the building from the outside and is terminated in an enclosure.
a) 25 ft
b) 30 ft
c) 50 ft
d) 100 ft
See answer and applicable Code reference
The correct answer is: c) 50 ft
Article 770 of the NEC applies to the installation of optical fiber cables, raceways, and cable routing assemblies. Part II of this Article covers cables located outside and entering buildings. As noted in 770.48(A), "Unlisted conductive and nonconductive outside plant optical fiber cables shall be permitted to be installed in building spaces, other than risers, ducts used for environmental air, plenums used for environmental air, and other spaces used for environmental air, where the length of the cable within the building, measured from its point of entrance, does not exceed 50 ft and the cable enters the building from the outside and is terminated in an enclosure."
