Protection of Direct-Buried Conductors

Dec. 8, 2014
Wiring method requirements for underground installations are outlined in Sec. 300.5 of the 2011 NEC.

Where direct-buried conductors and cables emerge from grade, they shall be protected by enclosures or raceways to a point at least _____ above finished grade.

a) 3 ft
b) 6 ft
c) 8 ft
d) 10 ft

See answer and applicable Code reference

The correct answer is: c) 8 ft

Wiring method requirements for underground installations are outlined in Sec. 300.5 of the 2011 NEC. As per 300.5(D)(1), "Direct-buried conductors and cables emerging from grade and specified in columns 1 and 4 of Table 300.5 shall be protected by enclosures or raceways extending from the minimum cover distance below grade required by 300.5(A) to a point at least 8 ft above finished grade. In no case shall the protection be required to exceed 18 in. below finished grade."

About the Author

Mike Holt

Mike Holt is the owner of Mike Holt Enterprises (www.MikeHolt.com), one of the largest electrical publishers in the United States. He earned a master's degree in the Business Administration Program (MBA) from the University of Miami. He earned his reputation as a National Electrical Code (NEC) expert by working his way up through the electrical trade. Formally a construction editor for two different trade publications, Mike started his career as an apprentice electrician and eventually became a master electrician, an electrical inspector, a contractor, and an educator. Mike has taught more than 1,000 classes on 30 different electrical-related subjects — ranging from alarm installations to exam preparation and voltage drop calculations. He continues to produce seminars, videos, books, and online training for the trade as well as contribute monthly Code content to EC&M magazine.

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