The three standard methods for testing fiber optic cabling are a visible light source, power meter and light source, and optical time domain reflectometer (OTDR). These fibers are most commonly made of glass and are very thin, typically less than a tenth of the width of a human hair. This test requires a special testing kit and protective eyewear, but it will help you diagnose problems with the cable's. We'll explain why it's vital to test fiber optic cables, the three most popular methods, and when you should use them. Just go to the topics below to find the information you.