Indoor fiber optic cable uses tighter buffers and routes through conduits or trays. Its ability to provide continuous temperature readings over long distances makes it an ideal solution for fire detection in tunnels. Recommendation ITU-T L. 100 describes characteristics, construction, test methods, and performance criteria of optical fibre cables installed by pulling method for duct and tunnel application. Note that Recommendation ITU-T L. 0, in February. Before applying protective measures, it's essential to understand the main risks fiber optic cables face outdoors. UV Exposure: Prolonged sunlight degrades standard plastic jackets, making them brittle. To ensure all specifications are met, consult the specific cable specification sheet for the cable you. e National Electrical Code (NFPA 70). If cables are installed in air ducts or plenums, the cable is to be fire re stant and have low smoke. To ensure the longevity and reliability of fiber optic cables in outdoor environments, it is crucial to protect them from various external factors.