Fiber optic cables should not be pulled or tugged excessively, as this can cause the fibers to become damaged or broken. As a premium brand dedicated to providing high-quality, finished optical network solutions, Gcabling has analyzed countless installation. The most common damage is a broken fiber, which is difficult to detect. But fibers can also be cracked from too much tension during cable pulling or despooling. The second most common problem is bending the fiber on Thomas Dooley, Fiber Specialists Inc. Twisting and kinking fiber optic cables can. Most fiber optic cables boast a pull strength of 100 – 200 pounds thanks to the internal kevlar or aramid yarn, known as the strength member. Once this happens, our bodies have no way of removing them.