This Standard applies to the following products designed to be employed in accordance with the Canadian Electrical Code, Part I:
a) nonmetallic outlet boxes, conduit, concrete, floor, and pull boxes that do not exceed 1640 mL in volume;
b) nonmetallic device boxes (with or without integral fittings) that do not exceed 1640 mL in volume, except for multiple-gang boxes where each single-gang section does not exceed 1640 mL in volume; and
c) extension rings, closure plugs, and outlet box covers.

This Standard also applies to requirements for metallic and nonmetallic box extenders intended for use with metallic or nonmetallic outlet boxes for wall or ceiling applications for installation in accordance with the Canadian Electrical Code, Part I. See Annex A.