WAC 296-800-28025. Maintain electrical fittings, boxes, cabinets and outlets in good condition

You must do the following when using covers and openings: (1) When conductors enter boxes, cabinets, or fittings: (a) Protect the conductor (wires) from abrasion. (b) Effectively close the openings where conductors enter. (c) Effectively close all unused openings. (2) Provide pull boxes, junction boxes, and fittings with covers approved for the purpose. (3) Make sure each outlet box has a cover, faceplate, or fixture canopy in completed installations. (4) Make sure covers for outlet boxes with openings for flexible cord pendants have bushings to protect the cord, or have a smooth and well rounded surface where the cord touches the opening. (5) Ground metal covers.