101 describes characteristics, construction and test methods of optical fibre cables for buried application. Note that Recommendation ITU-T L. (FOA) was founded in 1995 to help develop the workforce to build the fiber optic networks to support a rapid expansion in communications and the Internet. They define a minimum baseline of quality and workmanshi for installing electrical products and systems. Existence. Optical fibre cables - Part 3-10: Outdoor cables - Family specification for duct, directly buried and lashed aerial optical telecommunication cables IEC 60794-3-10:2015 which is part of a family specification, covers optical telecommunication cables to be used in ducts or direct buried. This part of IEC 60794 sets forth technical requirements and characteristics of single-mode optical fibre cables for duct and direct buried installation. This specification includes functional mechanical, environmental and optical requirements, recommended features and test methods for assessing. Underground fiber optic cable is designed for direct burial or conduit installation and is widely used in FTTH networks, backbone infrastructure, and industrial communication systems.