Standards, including National Electrical Code (NEC) in the US, the European Telecommunications Standards Institute (ETSI), and International Telecommunication Union (ITU), set recommendations or requirements for how deep to bury fiber optic cables. With international fiber networks predicted to grow to over 1. 8 million km in scope by 2025 (per TeleGeography), burying these cords of light comes with the benefits of avoiding cable damage, decreasing downtime, and extending their operational lifetime. The following are a detailed explanation: General Burial Depth: The burial depth of underground fiber. While local codes and soil conditions dictate specific requirements, general industry guidelines are: Standard Residential/Commercial Areas: 24 to 36 inches (60 to 90 cm) deep. Under Roadways or Driveways: 36 to 48 inches (90 to 120 cm) deep, often within a conduit for added protection. 6 meters for urban areas and 1. The depth at which cable lines must be buried is not a one-size-fits-all mandate. Federal. Recommendation ITU-T L. 101 describes characteristics, construction and test methods of optical fibre cables for buried application.