National Electrical Installation Standards

Standards as High as Your Own

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Wednesday, July 1, 2020

Question:

Hi Code Question of the Day,

What are the wiring requirements on wiring of a mechanics shop, can they be wired using nonmetallic sheathed cable where the wiring is covered in NEC Chapter 3?

William Martell

A

Answer:

Hello William,

Thanks for the question. The wiring requirements for commercial repair garages are located in Article 511. The wiring must meet the requirements in 511.4 which references Article 501 for Class I locations. The type of wiring required for a Class I, Division 1 or 2 location in a commercial repair garage must be in one of the wiring methods provided in 501.10(A) or (B). Nonmetallic sheathed cable is not permitted. See also Section 334.12(A)(4) which restricts NM cable for use in these locations.

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