UL 651

These requirements cover Schedule 40 and Schedule 80 extruded rigid PVC (polyvinyl chloride) electrical conduit, and fittings consisting of elbows and other bends made from and for use with this conduit. The designations "Schedule 40" and "Schedule 80" refer to USA trade sizes of conduit having iron-pipe-size outside diameters and specific wall thicknesses.

The following restrictions apply to use of the PVC conduit and fittings mentioned in 1.1:

1. Use at 50EC (122EF) and lower ambient temperatures
2. Use with 75EC (167EF) wiring, but the conduit and fittings may be used with 90EC (194EF) wiring if they comply with the construction (see Conduit for Use with 90EC Wire, Section 16) and marking (see 20.3 and 20.7 ? 20.8) requirements covering use with 90EC (194EF) wiring.

The conduit and fittings covered in these requirements are intended for use as rigid nonmetallic raceway for wires and cables in accordance with the National Electrical Code.