Which article focuses on boxes, enclosures, and fittings used in electrical installations?

• A. Article 334: Nonmetallic-sheathed cable (NM).
• B. Article 314: Boxes, enclosures, and fittings used in electrical installations.
• C. Article 320: Armored Cable (AC) usage and installation.
• D. Article 400: Flexible cords and cables.

Answer: (B)

The concept here is recognizing which NEC article governs the physical enclosures and fittings used in a wiring system. The article that focuses on boxes, enclosures, and fittings used in electrical installations is the one that sets the requirements for junction boxes, device boxes, weatherproof boxes, extension rings, and the clamps and fittings that accompany them, including box-fill calculations and proper installation practices. This article defines the scope for how these boxes and fittings are selected, installed, and sized for conductors and devices inside them. The other topics cover different wiring methods and components—nonmetallic-sheathed cable, armored cable usage and installation, and flexible cords and cables—rather than the general requirements for boxes and enclosures themselves. Therefore, the article dedicated to boxes, enclosures, and fittings is the correct focus.