As IP Security applications and other technology continues to demand increased bandwidth to manage large amounts of data, we have seen a rise in the use of fiber optic cables in between buildings as well as within structures. While many fiber cables on the market are ruggedized for outdoor installations, whether overhead, direct burial or within a conduit or duct, these cables have historically not carried the approval of the National Fire Protection Association, (NFPA) for indoor use. Thus, outdoor fiber cable being installed between structures typically had to be connected to NFPA indoor rated cable within a short distance of the outdoor cable entering the building. This connection and conversion to indoor cable required the mounting of a proper splice box and the splicing of the individual fiber strands from one cable to the other. Whether using a fusion splicer or mechanical splices, this conversion can add to equipment cost, installation time, and increases the optical loss of the fibers that have been spliced.
Fortunately, there is cable on the market that offers a unique combination of outdoor and indoor NFPA rated cable. This cable contains six strands of 50-micron OM3 laser-optimized fibers underneath a weatherproof outer jacket. The hybrid cable features a typical “distribution” fiber form factor with an aramid yarn protective layer under the outer jacket, and the individual fibers are encased in 900-micron plastic coatings. The outer diameter is less than ½ of a centimeter, and the jacketing is as flexible as typical indoor six-count distribution cable which eases many common installation issues.
Carrying the Optical Fiber Non-conductive-no metal, Plenum (ONFP) rated stamp from UL; this cable is ideal for use between buildings or structures. There is no longer the need for extra splices and protective boxes at each end of an outdoor fiber cable run which can save time and money on an installation.
There are two things to consider when planning to use this cable. Providing that the outdoor/indoor fiber cable you select does not have an internal crush protection layer, it is usable for overhead installation or can be run underground in a conduit or raceway. However, It should not be directly buried by itself. Also, it is recommended that you discuss using the cable with the end-user and possibly the local fire inspector to be sure they are aware that the cable is outdoor and indoor rated.
ADI is your trusted source for information if you have any questions regarding cable. As the industry’s leading cable and wire distributor, ADI sells over 109,000 miles of cable a year, enough to circle the Earth four times. ADI’s Systems Support Group is always here to help. You can contact the ADI Systems Support group at 1.800.ADI.SYS1