Article 314.15 (A): Damp, Wet or Hazardous (Classified) Locations
Damp or Wet Locations. In damp or wet locations, boxes, conduit bodies and fittings shall be placed or equipped within the box, conduit body or fitting. Boxes, conduit bodies and fittings installed in wet locations shall be listed for use in wet locations.
FPN No. 1: For boxes in floors, see 314.27 (C).
FPN No. 2: For protection against corrosion, see 300.6.
Article 100 defines the term weatherproof as “constructed or protected so that exposure to the weather will not interfere with successful operation.” Rainproof, rain tight or watertight equipment can fulfill the requirements for this definition where varying weather conditions other than wetness, such as snow, ice, dust or temperature extremes, are not a factor. A weather head fitting is considered to be weatherproof because the openings for the conductors are placed in a downward position so that rain or snow cannot enter the fitting.
See the definitions of damp location and wet location under location in Article 100, as well as the commentary following the definition of enclosure, for further explanation.
Article 314.16 (A): Number of Conductors in Outlet, Device, and Junction Boxes, and Conduit Bodies.
Boxes and conduit bodies shall be of sufficient 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.
FPN: For volume requirements of motor terminal housings, see 430.12.
Boxes and conduit bodies enclosing conductors 4 AWG or larger shall also comply with the provisions of 314.28.
(A) Box Volume Calculations The volume of a wiring enclosure (box) shall be the total volume of the assembled sections and, where used, the space provided by plaster rings, domed covers, extension rings, and so forth, that are marked with their volume or are made from boxes the dimensions of which are listed in Table 314.16 (A).
(1) Standard Boxes The volumes of standard boxes that are not marked with their volume shall be as given in Table 314.16 (A).
(2) Other Boxes Boxes 1650 cm3 (100 in.3) or less, other than those described in Table 314.16 (A), and nonmetallic boxes shall be durably and legibly marked by the manufacturer with their volume. Boxes described in Table 314.16 (A) that have a volume larger than is designated in the table shall be permitted to have their volume marked as required by this section.