Indoor/Outdoor Use Not Recommended


If this equipment was good enough for indoor use, someone must have decided why not place it outdoors as well. Big mistake! It’s obvious this junction box and EMT coupling and connector are not designed to be used outdoors in wet locations.

This basic junction box was used to connect a new underground nonmetallic conduit and new electrical metallic tubing (EMT). The EMT and box were mounted on the side of the building adjacent to a driveway and exposed to the outdoor elements. It appears the hole in the side of the box was made with a hole saw that was slightly larger than the EMT fitting. To close the gap, the installer first sealed it up with silicone and then wrapped some plastic around it.

Not only does this installation violate the listing and labeling requirement of this equipment, as per 110.3(B), but it also violates the grounding and bonding requirements of 250.118.

As noted in 358.10(C), “All supports, bolts, straps, screws, and so forth shall be of corrosion-resistant materials or protected against corrosion by corrosion-resistant materials.” An informational note after this text steers you to Sec.300.6 for details on protection against corrosion.

Section 358.42 addresses the use of EMT couplings and connectors. The last sentence in this section states, “Where installed in wet locations, they shall comply with 314.15.” Article 314 addresses outlet, device, pull, and junction boxes; conduit bodies; fittings; and handhole enclosures. Section 314.15 states, “In damp or wet locations, boxes, conduit bodies, and fittings shall be placed or equipped so as to prevent moisture from entering or accumulating within the box, conduit body, or fitting. Boxes, conduit bodies, and fittings installed in wet locations shall be listed for use in wet locations.”