314 – Outlet, Device, Pull and Junction Boxes; Conduit Bodies; Fitting; and Handhole Enclosures

314.16(B)(5) – Volume Allowance for EGCs and Equipment Bonding Jumpers

Change at a Glance:

Volume allowance for EGCs and equipment bonding jumpers was revised to add an additional ¼ volume allowance to the existing single volume allowance. New ¼ volume allowance to be counted in installations with more than four EGCs or equipment bonding conductors.

314.16 Number of Conductors in Outlet, Device, and Junction Boxes, and Conduit Bodies.

Boxes and conduit bodies shall be of an approved size to provide free space for all enclosed conductors. In no case shall the volume of the box, as calculated in 314.16(A), be less than the fill calculation as calculated in 314.16(B). The minimum volume for conduit bodies shall be as calculated in 314.16(C).
The provisions of this section shall not apply to terminal housings supplied with motors or generators.
Boxes and conduit bodies enclosing conductors 4 AWG or larger shall also comply with the provisions of 314.28. Outlet and device boxes shall also comply with 314.24.

(B) Box Fill Calculations. The volumes in paragraphs 314.16(B)(1) through (B)(5), as applicable, shall be added together. No allowance shall be required for small fittings such as locknuts and bushings. Each space within a box installed with a barrier shall be calculated separately.

(5) Equipment Grounding Conductor Fill. Where one or more up to four equipment grounding conductors or equipment bonding jumpers enter a box, a single volume allowance in accordance with Table 314.16(B) shall be made based on the largest equipment grounding conductor or equipment bonding jumper present in entering the box. Where an additional set of equipment grounding conductors, as permitted by 250.146(D), is present in the box, an additional A ¼ volume allowance shall be made for each additional equipment grounding conductor or equipment bonding jumper that enters the box, based on the largest equipment grounding conductor in the additional set or equipment bonding conductor.

314.27(C) – Outlet Boxes for Support of Ceiling-Suspended (Paddle) Fan

Change at a Glance:

Revision will now generally require all outlet boxes mounted in a location acceptable for the installation of a ceiling-suspended (paddle) fan in the ceilings of habitable rooms of dwelling units to be listed for the sole support of ceiling-suspended (paddle) fan.

314.27 Outlet Boxes

(C) Boxes at Ceiling-Suspended (Paddle) Fan Outlets. Outlet boxes or outlet box systems used as the sole support of a ceiling-suspended (paddle) fan shall be listed, shall be marked by their manufacturer as suitable for this purpose, and shall not support ceiling-suspended (paddle) fans that weigh more than 32 kg (70 lb). For outlet boxes or outlet box systems designed to support ceiling-suspended (paddle) fans that weigh more than 16 kg (35 lb), the required marking shall include the maximum weight to be supported.
Where spare, separately switched, ungrounded conductors are provided to a ceiling-mounted outlet box, Outlet boxes mounted in the ceilings of habitable rooms of dwelling occupancies in a location acceptable for the installation of a ceiling-suspended (paddle) fan in one-family, two-family, or multifamily dwellings, the outlet box or outlet box system shall be listed for sole support of a ceiling-suspended (paddle) fan comply with one of the following:
(1) Listed for the sole support of a ceiling-suspended (paddle) fans
(2) An outlet box complying with the applicable requirements of 314.27 and providing access to structural framing capable of supporting of a ceiling- suspended (paddle) fan bracket or equivalent.