Code Change Summary: The definition of Accessible has been expanded.

Wiring methods are considered accessible if they are capable of being removed or exposed without damaging the building structure or finish or not permanently closed in or blocked by the structure, other electrical equipment, other building systems, or the building finish.

Conductors and devices within boxes, conduit bodies, and other enclosures are all considered wiring methods.

NEC Section 314.29 requires boxes, conduit bodies, and handhole enclosures to be installed so that wiring and devices contained in the boxes, conduit bodies, or handhole enclosures can be rendered accessible. To find out exactly what that means requires an understanding of the word “accessible” as defined in Article 100.

Previously, the definition of “accessible”, as applied to wiring methods, simply meant that the enclosed conductors and devices must be “capable of being removed or exposed without damaging the building structure or finish or not permanently closed in by the structure or finish of the building”.

In the 2023 NEC^®, the definition of Accessible (as applied to wiring methods) has been modified and now specifically mentions other items that could prevent access to the wiring methods.

Sometimes other electrical equipment, building elements, or other systems might “block” access to an enclosure containing wiring. HVAC systems, plumbing systems, or even electrical conduits should be installed so they don’t block access to a wiring method such as a junction box.

The intent of Section 314.29 and the definition has always been to make sure wiring and devices within an enclosure can be accessed at any time for troubleshooting, maintenance, or repair.

Below is a preview of the NEC^®. See the actual NEC^® text at NFPA.ORG for the complete code section. Once there, click on their link to free access to the 2023 NEC^® edition of NFPA 70.