Which cable construction is best suited for long outdoor installations due to decoupling of fiber from tensile stresses?

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Decoupling the fiber from tensile stresses is achieved by placing the fiber in a loose tube inside the cable. In a loose-tube design, each fiber runs in its own small tube that isn’t tightly bonded to the outer jacket, and the tube is surrounded by strength members (like aramid yarn) while the fibers themselves aren’t pulled directly when the cable is tensioned. This means installation tension, bending, and thermal movement are absorbed by the outer jacket and the tube assembly rather than stressing the glass fiber, reducing risk of attenuation and micro/macro-bending losses on long outdoor runs. Tight-buffered constructions bind the fiber more rigidly to the protective layer, so tensile loads transfer more directly to the fiber, which isn’t ideal for long outdoor installations with significant tension. Armor options add protection but increase stiffness and weight, and don’t provide the same stress decoupling as loose-tube designs. Therefore, the loose-tube construction is best for long outdoor installations.