NEMA TC 2-2013 covers the following types of Electrical Polyvinyl Chloride (PVC) Conduit (EPC), which may be constructed of single, solid layer of PVC, or may be constructed of multiple layers of PVC, one of which may be cellular (foamed) PVC. The designations "40" and "80" refer to Schedules 40 and 80 (EPC- 40 and EPC-80), respectively, of Iron Pipe Size (IPS) dimensions. Common uses for these designations are: a) EPC-40 -Electrical conduit designed for normal-duty applications aboveground; concrete-encased applications or direct burial. May be referred to as "heavy wall." b) EPC-80 -Electrical conduit designed for heavy-duty (areas of physical damage) applications aboveground; concrete-encased applications or direct burial. May be referred to as "extra heavy wall." Note: The values stated in U.S. customary units are to be regarded as the standard. NEMA TC2-2013 does not fully address elbows and fittings. See NEMA TC3-2013.