NESC conduit burial depth requirements?

[rockman7892]

Does the NESC have any specific requirements for 34.5kv pvc conduits encased in concrete ductbank beyond what is required by NEC?

NEC allows for 24” min burial depth for MV pvc conduits that are encased in 2” of concrete. Does the NESC require any greater burial depths?

 

[Paulsey88]

rockman - The NESC is not nearly as prescriptive on conduit depths as the NEC. In fact it is quite vague and the NEC can sometimes be used as a general guide for many installations that would fall under the jurisdiction of the NESC. That being said - Rule 322A3 states that you must consider loading from external forces (surface loads) for conduit that is less than 3ft. 36" min. is good practice for primary (2.4kV) and up. Additionally, depending on where you are at in North America, this may put you below frost and mitigate frost heave issues for horizontal runs.