1.1 These requirements cover strut-type channel raceways and fittings for use only in dry locations and in accordance with the National Electrical Code, NFPA 70.
1.2 Strut-type channel raceways of the following thicknesses are intended to enclose circuits operating at potentials not exceeding 600 volts between conductors:
a) Strut-type channel raceways that are entirely of metal having a channel (base) at least 0.071 inch (1.81 mm) thick and a metal closure strip (cover) at least 0.040 inch (1.02 mm) thick.
b) Strut-type channel raceways consisting of a nonmetallic closure strip (cover) on a metal channel (base) of the thickness indicated in 1.2(a).
1.3 These requirements do not apply to cable trays, wireways, or surface metal or nonmetallic raceways.
UL 5B references these Standards:
5A *
20 *
498 *
514A *
. Table of Contents for UL 5B.