After fiber optic cables are installed, spliced and terminated, they must be tested. As the components like fiber, connectors, splices, LED or laser sources, detectors and receivers are being developed, testing confirms their performance specifications and helps. For every fiber optic cable plant, you will need to test for continuity, end-to-end loss and then troubleshoot the problems. If it's a long outside plant cable with intermediate splices, you will probably want to verify the individual splices with an OTDR also, since that's the only way to make. 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). Using a visible light source tests the continuity of fiber optic cabling. Key tests include: Effective fiber testing utilizes advanced tools such as Optical Loss Test Sets (OLTS), Optical Time-Domain Reflectometers (OTDR), and Visual Fault. Fiber optic tools are specialized instruments designed for installing, terminating, splicing, testing, and maintaining fiber optic cables. The Contractor must utilize the correct equipment and testing techniques to gain acceptance, or the work cannot be approved.