314.28 Pull and Junction Boxes Requirements pertaining to the installation and use of all boxes and conduit bodies used as outlet, device, junction or pull boxes are in Article 314 of the National Electrical Code (NEC).
Jim Dollard has an extensive background in codes and standards. If you have a query about the National Electrical Code (NEC), Jim will help you solve it. Questions can be sent to firstname.lastname@example.org. Answers are based on the 2014 NEC. Unsupported raceways