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Illustrated Catastrophes: Suspended Ceiling Surprise

Oct. 5, 2020

Think you know how these installations violate the NEC?

All references are based on the 2020 edition of the NEC.

Suspended Ceiling Surprise

I typically like surprises, but not when they smack me in the head while I’m removing suspended ceiling tiles. This junction box was just resting on top of the ceiling tile, and it fell right out when I slid the tile over. Surprise! Boxes must be supported in accordance with one or more of the methods specified in Sec. 314.23(A) through (H). These methods include securely fastening the box to a surface; rigid support in the form of a brace; using nails or screws to fasten the box; using clamps, anchors, or other identified fittings; or even using support wires. There are no Code rules that permit simply resting the box on top of a removable ceiling tile. Installing a box in this manner could cause physical harm to the unsuspecting worker who moves that ceiling tile. It also could have startled me to the point where it knocked me off my ladder and led to serious injuries. Thankfully, this event did not result in any injuries. Another problem is the lack of cover for this box. Section 314.25 requires a cover, faceplate, lampholder, or luminaire canopy to be installed for a completed installation.

No Cover. No Clamps. No Good!

This installer apparently believes covers and cable clamps are overrated. Who needs them when it’s easier to simply stuff the cables right into the box? Section 314.17(B)(2) requires these wiring methods to be secured to the box. Using MC cable with a nonmetallic box is permitted only where internal bonding means is provided for bonding the metal cable jacket as permitted in Sec. 314.3, Exception. The green equipment grounding conductor (EGC) of the MC cable is connected to nothing. It is cut off and just floating there. It concerns me to think that an installer would ignore all the rules of Art. 250 and purposely leave equipment unbonded and ungrounded. Section 300.10 requires metal raceways, cable armor, and metal enclosures to be metallically joined to form an electrically continuous conductor. That same Section also requires cable assemblies to be mechanically secured to each box, fitting, cabinet, or enclosure. Section 330.30(B) requires this MC cable to be secured within 12 in. of this box. For supporting the UF cables, Sec. 225.21 directs to Sec. 230.51, which requires the UF cables to also be secured within 12 in. of the box. The missing cover violates Sec. 314.25.

About the Author

Russ LeBlanc | Owner

Russ started in the electrical trade as an apprentice in 1985. He worked his way up to become a Journeyman Electrician and then eventually became a Master Electrician and Licensed Construction Supervisor. In 1999 Russ become an Electrical Instructor for The Peterson School of Engineering in Massachusetts where he developed his passion for teaching, and quickly became Department Head of Electrical Instruction. Russ has taught thousands of apprentices, electricians, engineers, inspectors, and other electrical professionals during his career as an instructor. He continues to provide electrical professionals with Electrical Code seminars, Arc-Flash Awareness training seminars and educational material through his LeBlanc Consulting Services in North Reading, MA whose specialty is educating electricians. He has been an active member of the NFPA Electrical Section and has authored hundreds of National Electrical Code proposals and comments which have become Code rules to improve the safety for the electrical industry. Russ is also an IAEI certified Electrical Inspector.

Please visit www.russleblanc.net for more information.