Typically, the insertion loss should not exceed 0.75 dB and the return loss should be higher than 20 dB. Typical insertion repeatability, the difference in insertion loss from one plug to another, is 0.2 dB.

On all connectors, cleaning the ceramic ferrule before each connection helps prevent scratches and increases the life of the connector.

Connectors on PM fibers are sometimes marked with a blue strain relief sleeve or connector body. Sometimes blue buffer tubes are used on fibers.

Hardened fiber optic connectors (HFOC) and hardened fiber optic adapters (HFOA) are passive telecommunications components used in outdoor factory environments. They provide direct connections to customers from fiber optic distribution networks. These assemblies can be installed in pedestal closures, aerial and flush closures and terminations, or in equipment located at the customer's premises, such as fiber distribution hubs (FDHs) or optical network termination units.

These connectors are field-mateable and ruggedized for use in OSPs to support fiber-to-the-premises (FTTP) deployments and service offerings. The HFOC is designed to withstand existing climate conditions across the United States, including rain, floods, snow, icy, high winds, and ice storms. The ambient temperature range is −40°C (−40°F) to 70°C (158°F).

Telcordia GR-3120 contains the industry's latest general requirements for HFOC and HFOA.