Is there a standard that requires fiber to be in inner duct in its own duct separate from copper cables? We have a contractor that pulled 148 strands dialectic fiber and 400 pair copper through same duct bank and want him to separate them. He pulled inner duct as part of the project but did not use it. He has created a maintenance issue and says show me the standard that has to have separate paths/ducts/inner ducts. I can not find it in the TIA, hopefully someone smarter than me already knows it and can reference it for me.