All connections should be _____ prior to testing.

Cleaning all connections prior to testing is essential for ensuring accurate results and optimal performance in fiber optic networks. Dust, dirt, and other contaminants can significantly affect the integrity of the optical signal and lead to misleading test results or even damage to the equipment. When connectors are not clean, the attenuation (signal loss) will increase, and the overall performance of the fiber optic link can be compromised.

The process of cleaning typically involves using specialized cleaning tools and solutions designed for optical fibers to remove any contaminants without damaging the connectors. This step is fundamental to establishing reliable connections and preventing potential issues in the network, such as increased insertion loss or back reflections.

While other processes like cleaving, conditioning, and polishing may also play roles in fiber optic installation and maintenance, they focus on preparing the fiber ends for connection or improving the physical attributes of the connections. However, these processes do not replace the necessity of cleaning as a pre-testing step to ensure effective communication capability within the fiber optic system.