National Electrical Installation Standards

Standards as High as Your Own

Tuesday, July 17, 2018


For a structure with openings at both ends and a concrete floor that trucks that weigh between 50,000 lbs and 100,000 lbs drive through does article 300.5 apply? (Is it considered a drive way?)

Clyde Saunders



Hey Clyde thanks for your question. Underground installations are covered by 300.5 and Table 300.5 indicates that under a building the cover requirements are "0" in the third row of locations. The word "driveway" is not defined in the NEC but standard dictionaries indicate that it is a type of road leading to a building or structure so it does not seem to apply within the structure. But if subject to physical damage conductors, raceways, and cables must be protected as stated in 300.4. And 50,000-pound trucks would seem likely to cause physical damage.

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