ajhill
Member
In this code it states that if the conduit is 24 inches below grade it can be non metalic rigid. I had I M C to within 2 feet of the final connection and 20 inches in depth to the I M C in a column. I proceeded to put the 2 ends of the pipe together with a piece of rigid nonmetalic conduit. The whole connection was going to be encased in cement and not a part of the path for vehicle traffic. I see that the code requires metalic rigid or I M C. The thought came to mind seeing that there is a requirement that says the last ten feet of conduit needs to be metalic either rigid or I M C, so I thought it was for a earth ground, but that was not, because you can use nonmetalic at 24 inches. So why is required to use a metalic conduit at twenty inches and not 24 inches, or does the requirement of a metalic rigid or I M C for the last 10 feet of conduit where exiting the earth take precedence, and even so why.