Nowadays, optical communications are the most requested and preferred telecommunication technology, due to its large bandwidth and low propagation attenuation, when compared with the electric transmission lines. Besides these advantages, the use of optical fibers often represents for the telecom operators a low implementation and operation cost. Moreover, the applications of optical fibers goes beyond the optical communications topic. The use of optical fiber in sensors applications is growing, driven by the large research done in this area in recent years and taking the advantages of the optical technology when compared with the electronic solutions. However, the implementation of optical networks and sensing systems in seashore areas requires a novel study on the reliability of the optical fiber in such harsh environment, where moisture, Na+ and Clions are predominant. In this work we characterize the mechanical properties, like the elastic constant, the Young modulus and the mean strain limit for commercial optical fibers. The fiber mean rupture limit in standard and Boron co-doped photosensitive optical fibers, usually used in fiber Bragg grating based sensors, is also quantify. Finally, we studied the effect of seawater in the zero stress aging of coated optical fibers. Such values are extremely relevant, providing useful experimental values to be used in the design and modeling of optical sensors, and on the aging performance and mechanical reliability studies for optical fiber cables.