Abstract: A fiber optic ferrule assembly has an elongated ferrule body on a major axis and having a rear end opposite its free end. The body has a passage extending from a rear aperture at the rear end to a foreword aperture at the front end. A cable extending from the rear end of the ferrule has several optical fibers extending to the forward end. The ferrule has several alignment features, each closely receiving a fiber. A hermetic sealant applied to the alignment features to provide a hermetic seal. The sealant may be applied via a lateral access aperture, which may be sealed by the sealant. The ends of the passage may be sealed by different materials, and the cable may have a jacket that is partially received in the ferrule.