:: Duct/Innerduct materials and colors: Fiber ducts are usually made from HDPE (high-density polyethylene), PVC or other compound. They are usually in black or gray. Fiber innerduct is usually orange or yellow. :: Why usually ...

The two most common outdoor fiber optic cable installations are pole line aerial installation and underground cable installation. Underground cable installation can be buried directly underground or placed into a buried duct. Direct burial installation: ...