29 requires that you be able to reach the wiring inside by simply removing a cover plate or access panel. The National Electrical Code (NEC) governs electrical junction box rules. These rules define when you must install a box, how large it must be, how you must install it, and how inspectors evaluate compliance. A junction box has many functions: It is essential to secure. Junction boxes must remain accessible after installation without tearing into the building's structure. This means you cannot permanently bury a box behind drywall, plaster. The NEC code of junction box has rules for how boxes are made and put in. Non‑compliance risks safety or code violations.
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