Exterior ENT installation

What’s Wrong Here? Hint: Exterior ENT Installation

Dec. 28, 2023
Think you know how this installation violates the NEC?

Hint: Exterior ENT installation

That loop of blue raceway in the photo is Electrical Nonmetallic Tubing (ENT). ENT is often referred to a “Smurf Tube” due its blue coloring matching the color of the Smurf cartoon characters. Installing ENT on the exterior of a building is not one of the wiring methods permitted in Sec. 225.10 for outside branch circuits and feeders. I was only able to see this from the street level, so I am not 100% sure what this ENT is being used for, however, Sec. 362.12(7) prohibits ENT from being installed where it is exposed to the direct rays of the sun unless it is identified as being sunlight resistant. I’m not sure if there is any ENT that is identified as being sunlight resistant. Where nonmetallic equipment is exposed sunlight, Sec. 300.6(C)(1) requires raceways, cable trays, cablebus, auxiliary gutters, boxes, cables with a nonmetallic outer jacket and internal metal armor or jacket, cable sheathing, cabinets, enclosures, elbows, couplings, nipples, fittings, supports, and support hardware to be either listed as being sunlight resistant or identified as being sunlight resistant.

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.

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