National Electrical Installation Standards

Standards as High as Your Own

Tuesday, December 19, 2017


Re: CQD answer published Friday, December 8, 2017 -Physical Damage Protection

In regards to 300.4 and the required 1.25” separation from edges – the Exhibit 300.2 in the handbook shows romex run on the bottom of what appears to be floor joists. Does this violate the 1.25” separation?




Hey Allen thanks for your follow up question. Exhibit 300.2 in the 2017 NFPA NEC Handbook is an example of an acceptable installation. The wording in 300.4(D) is "parallel to framing members and furring strips". The furring strips in Exhibit 300.2 are what the ceiling finish material will be secured to so the NM cables need to be 1 1/4 inch from them as they are shown.

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