Long-term reliability of transmission loss in optical fiber cables

Increased optical-fiber cable losses due to hydrogen are discussed. A mathematical model is developed to predict the growth of hydrogen concentration in the cable, which is determined by the evolution from organic cable materials and permeation through the cable sheath. This cable model, together with the measured parameters for the cable materials, explains the measured results. Design criteria for the allowable hydrogen evolution from cable materials and for the cable sheath structure are established on the basis of the model