All references are based on the 2023 edition of the NEC.
A Creative Wiring Solution
While this installation does show some creativity and imagination, using what appears to be gas piping or gas pipe fittings as a wiring method is not recognized by the Code. Section 110.8 informs us that only suitable wiring methods are included in the Code. There is no Article in Chapter 3 covering gas piping as a wiring method. The box installed for the luminaire is not suitable for this outdoor wet location and does not comply with the requirements of Sec. 314.15. Boxes installed in wet locations such as this must be listed for use in wet locations. The manner in which this box is supported does not comply with any of the provisions specified in Sec. 314.23(A) through (H). Section 314.23(F) Exception No. 2 provides very specific requirements for using one threaded intermediate metal conduit (IMC) or rigid metal conduit (RMC) for the support of a box, but this installation does not comply with those requirements. The cover on the lower box where the photocell is mounted is only secured to the box with one screw, does not provide a weatherproof enclosure, and allows moisture to enter the box. This loose cover does not comply with Sec. 314.15 either.
A Common Site in Garages
Section 334.10(1) permits NM cable to be installed in attached and detached garages of one- and two-family dwellings. This installation shows the inside of an attached garage for a dwelling unit. It’s quite common for me to see installations very similar to this one where NM cable is exposed in the open walls, and storage items or tools get placed against the walls or in contact with the NM cable. In this case, large citronella candles were stuffed behind the cables running horizontally through the studs of the exterior walls. Some Code users would argue that NM cable should not be installed here, as it is exposed to physical damage, but there is no wording in Sec. 334.12 that specifically prohibits this installation. For exposed work, Sec. 334.14(C) requires the cable to be protected from physical damage by being installed in RMC, IMC, electrical metallic tubing (EMT), Schedule 80 PVC conduit, RTRC-XW, or other approved means where necessary. Is that type of protection necessary here? This question is often a topic of debate between electricians and inspectors who think that it’s best to err on the side of caution when it comes to electrical installations.