The direct-buried fiber optic cables allow underground laying without usage of additional pipes. The cables stand up with added mechanical protection, moisture resistance, and environmental and biological hazards to rodents, termites, and fire. Its structure is mainly composed of cable core, longitudinal covering a layer of two-sided synthetic mica tape outside cable core, inner sheath packed with ceramic sheathing. Corning Optical Communications manufactures quality flame retardant optical fiber cables for indoor applications, which comply with the requirements of the National Electric Code® (NEC® 2023) published by the National Fire Protection Agency (NFPA). To ensure compliance to these requirements, a. einforced Plastic (FRP) armouring. This brings flexibility and lower bending radius tha provides a high rodent protection. The design is reirial environments. The outer sheath is made from black UV-stabilized and weather resistant material which is SHF1 classified, and may be exposed for shorter periods to fluids such as diese and mineral oils.