While there are several specific types of listings for power cables, specifically for tray applications, there is no equivalent tray rating for optical fiber cables. 770 references sections in Chapter 2 and Art. 22, which applies when. Answer: No. NEC section 300-8 does not permit any tube, pipe, or equal for water, air gas, drainage, steam, or any service other than electrical in raceways or cable trays containing. Fiber optic cable may be installed indoors or outdoors using several different installation processes. Outdoor cable may be direct buried, pulled or blown into conduit or innerduct, or installed aerially between poles.