The impact of hydrogen (H₂) on standard single-mode optical fibers representsa significant issue in optical telecommunication systems. This influence may be caused by the diffusion of H₂ atoms directly into the silicon (Si) structure of the optical fibers or by the formation of OH ions at locations where the fiber surface is damaged. An optical link consists of cable sections and splices of optical cables within the cable infrastructure. Splice points located in optical protective closures represent the weakest links in the chain. This paper analyzes the resistance of these weakest links in the optical link chain. The greatest degradation at splice points is caused by water. If water penetrates the closure, it can come into direct contact with the fibers. Contact occurs in areas of the fibers protected by a polymer coating and in spots where surface damage has occurred due to the stripping of the polymer protection layer. The first chapter investigates the causes of parameter degradation in optical fibers at splice points. The second chapter defines the testing model. Fiber samples were then analyzed using a microscope. The decisive factor that determines the lifetime of optical cables is defined in the conclusion. Recommendations are provided for repairing this degradation and extending the service life of optical fibers, contributing to a techno-economic analysis of the optical cable lifetime.