The short answer, based on general industry standards and the National Electrical Code (NEC), is that fiber optic cable is typically buried between 24 inches (60 cm) and 30 inches (76 cm) deep. However, simply hitting this depth isn't enough to guarantee your network survives. Underground cables are pulled in conduit that is buried underground, usually 1-1. 2 meters (3-4 feet) deep to reduce the likelihood of accidentally being dug up. In extreme cold climates, cables may need to be buried at greater depths where there temperatures are colder and frost penetrates to. Compared to aerial routes, buried fibers are better protected against wind, lightning, ice, falling trees, vehicle impact and vandalism. They also remove visual clutter from urban skylines. For project owners and OSP designers, the key decision is not only whether to bury fiber, but how to choose. The Fiber Optic Association, Inc. While burying is common for durability, aerial deployment and even indoor use are viable, offering flexibility based on your specific needs and environment.
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