FO Connector Contamination – A Constant Threat

Fiber optic communication most commonly works in duplex or multifiber transmission by transmitting light to a receiver in one direction on a fiber and receiving transmitted light back to a second receiver on the second fiber. Most engineers can understand that and also the fact that anything in that light path will degrade the amount and quality of light, but fail to appreciate how easy it is for that path to become contaminated.   Contamination of connector end faces can have a significant impact on network performance, as applications that run over fiber have a power budget which becomes smaller the higher the speed of the application such as 10G Ethernet and beyond.

Studies have shown that when asked what the primary cause of fiber network failures are, 98 percent of installers respond that it is down to contamination on the end faces of the fiber.

When undertaking installations, technicians understand the importance of cleanliness of the installation in patch panels, ready for testing, but then when patching occurs, that reasoning seems to evaporate.

A brand new patch cord removed from its packaging is probably not clean. It might come in a sealed plastic bag with end caps on the ferrules of the fiber connectors, but the chances are static electricity will attract dirt to the fiber end as the end caps are removed. Not only that, when patching fiber cords in it is very easy for the installer to touch the end of the fiber connectors, or accidentally drop one end on the floor while the other end is being patched in. It is not unknown for an installer to drop a patch cord and instinctively blow the ‘dust’ off the end of the connector before installing it.

An installer will have checked and tested the fiber installation prior to patching the cords so their response will be ‘It was good when I tested it!’

In addition, 80 percent of network owners stated the same cause. Once the network is installed and running, problems occur when moves, adds and changes happens and again contamination on the connectors end faces is the most common cause.

Contamination of fiber optic connector endfaces is a constant threat, and at every opportunity they should be inspected and cleaned if necessary.