Loss stability assurance against hydrogen for submarine optical fiber cable

Hydrogen generation resulting from electrochemical reactions between cable metals and condensed water or moisture permeated through the cable jacket was studied. It was found that hydrogen generation increases exponentially as time elapses and tends to saturation after about one month. Partial pressure distribution along the cable of hydrogen generated in the immersed range of a damaged cable was analyzed by means of the diffusion equation and the optical loss increase was estimated. It was shown that a water-blocking resin effectively prevents water penetration and hydrogen diffusion along the cable