Choosing the wrong cable outer sheath material can cause early issues like cracking or swelling. Common materials include PVC, PE, LSZH, PUR, and rubber, each with different strengths. Understand the Environmental. What Is a Cable Sheath and Why It Matters 🔍 The cable sheath is the outer protective layer of a fiber optic cable. Its primary functions include: While the optical fiber itself remains largely unchanged, the sheath material determines how the cable behaves in fire scenarios, outdoor environments. The main function of the fiber cable outer sheath is to protect the optical fibers in the optical cable from external damage. At the same time, it must have. Whether you are designing and manufacturing a new cable or simply choosing an existing one for data, power, fiber optics, or industrial automation, the outer sheath (jacket) is much more than just a speaking cover to the eye; it is, in fact, an important job holder in mechanical protection. Optical fiber cables are generally composed of optical fiber cores, cladding, coatings, reinforcing elements, and outer sheaths. It can provide mechanical, moisture-proof, fireproof, anti oxidation, and chemical protection for the conductors inside the cable, protecting the cable.