Important Points

Before you begin cleaning, always inspect the fiber connections.
Inspect and clean both fiber ends every time you make a connection.
Keep a protective cap on unplugged fiber connectors.
Do not touch the end of a fiber.
Store unused protective caps in a clean resealable container, located nearby for easy access.
Do not reuse cleaning tissues or swabs.
Do not allow alcohol or another wet cleaning agent to dry on a fiber end.
Never touch the dispenser tip of an alcohol bottle or any clean portion of a tissue or swab.
Use care when handling the fiber; do not twist or pull.
Keep your cleaning fluids away from open flame or spark.

The figure below describes the acceptable limits of defects in a fiber connection.

Fiber Optic Cross-Section