For fibers installed without excessive mechanical stress, the expected lifespan exceeds 100 years. The acrylate coating (250 µm primary coating) surrounding the silica is more sensitive: exposed to UV, humidity or extreme temperatures, it can become brittle over 10 to 20 years. When you invest millions in a fiber optic cable network, you are buying a long-term asset. Some fiber optic cables fail in 5 years, turning. How long does fibre optic cable last for? With proper installation, fibre optic cables have a service life of around 25 years, but in practice, can perform for far longer.