This can be done with several techniques, e. sheaves, quadrants or flexible ducts. Those should be large enough to allow the cable to be stored with loops larger than the recommended bend . This article provides a practical, installation-focused guide to fiber bend radius, including definitions, standards, common mistakes, and best practices. What Is Fiber Optic Bend Radius? The fiber optic bend radius refers to the smallest radius a fiber cable can be bent without causing. Fiber optic cables are designed to withstand some bending, but excessive bends can physically damage the glass fiber or cause significant signal loss. That's why every fiber cable has a minimum bend radius specification provided by the manufacturer.