Historical
NEMA TC 2:2003
Electrical polyvinyl chloride (pvc) conduit
Covers electrical PVC conduit of types EPC-40 designed for normal-duty applications above ground and concrete encased applications or direct burial, and EPC-80 designed for heavy-duty (areas of physical damage) applications above ground and concrete encased applications or direct burial.
NEMA: National Electrical Manufacturers Association [nema]