In sensing applications, the potential of signal noise must be eliminated. Sheathings designed to be totally opaque (PVC, silicone) should be considered, and in the case of multi-channel construction, both sender and receiver fibers s. In sensing applications, the potential of signal noise must be eliminated. Sheathings designed to be totally opaque (PVC, silicone) should be considered, and in the case of multi-channel construction, both sender and receiver fibers should be individually sheathed inside a larger common sheathing. While it has nothing to do with sheathing, don't ov. Glass fiber and plastic fiber is fragile. When individual fibers break, light transmission and uniformity are reduced. After the first few fibers break at a stress point, a chain reaction occurs, hastening the destruction of the part. Surrounding fiber with a jacket or sheathe protects it from abrasion. Sheathing typcially has a larger bend radius,. For applications requiring minimal handling, where the application is illumination, and heat exposure is low, consider inexpensive PVC sheathing. PVC offers good protection from corrosive mists and foreign debris, as well as protection from incidental abrasion and contact. This material is also manufactured in corrugated shape, offering some crush. For repeated handling, where the application is illumination, and heat exposure is low, consider monocoil, which provides moderate crush and kink resistance in addition to debris protection. This choice is lighter and more flexible than SL type sheathing. In addition, it's available in many more ID/OD selections, making an efficient and cost effect. For repeated handling around big equipment, where heavy objects can fall on, roll over, or simply compress the component, and where the application is illumination, and heat exposure is low, consider PVC covered stainless interlock (SL), which provides the best crush and kink resistance in addition to debris protection. This material is the most ex.