This is a new edition of UL 5A.

Scope

1.1 These requirements cover nonmetallic raceways and fittings. These products are for use as surface wiring systems in accordance with the National Electrical Code (NEC) and Canadian Electrical Code (CEC), Part I.
1.2 Raceways that are all nonmetallic and of any thickness are intended to enclose circuits operating at potentials not exceeding 600 V between conductors.
1.3 Nonmetallic raceways with metal covers are intended to enclose circuits operating at potentials in accordance with Table 1 or Table 1a.
1.4 These requirements do not cover surface metal raceways, cable trays, or wireways.