When NM cable is installed through metal framing members, what must be utilized for protection?

When NM (non-metallic) cable is installed through metal framing members, it is important to use listed bushings or grommets to provide protection. This is necessary because metal framing can have sharp edges that might damage the outer sheath of the NM cable. If the cable’s sheath is compromised, it can lead to electrical hazards, including short circuits or potential shock hazards.

Listed bushings or grommets act as a protective barrier between the cable and the metal framing, ensuring that the cable insulation remains intact and preventing wear and tear that could arise from metal edges. The use of these protective components is part of maintaining safe installation practices according to electrical codes and standards.

Other options like cable ties do not provide adequate protection against sharp edges, and while conduits offer a method of protection, they are not always necessary or appropriate for all installations involving NM cable. The option stating that no protection is needed does not consider the risks associated with metal framing, where even minor abrasion can lead to significant electrical risks. Therefore, utilizing listed bushings or grommets is the correct approach to ensure the safe installation of NM cable through metal framing members.