National Electrical Installation Standards

Standards as High as Your Own

Thursday, November 10, 2022


Good morning “Code Guru”, Do all electrical installations need to be Approved/Listed? All the Best, James Vollrath


Hello James, thanks for the question. Yes, and maybe. Section 110.2 states: conductors and equipment required or permitted by the NEC® shall only be acceptable if “Approved”. Section 110.3 provides guidance to an AHJ on what methods can be utilized to comply with the approval required in Section 110.2. AHJ’s can use one or more of the following methods for determining approval:

  • Examination (Section 110.3(A)(1)-(8))
  • Installation and Use (Section 110.3(B))
  • Listing (Section 110.3(C))


Listing of equipment would also be required, where specifically mandated in the Code. For example: Section 242.8 requires SPDs to be listed devices.

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IMPORTANT NOTICE: Unless the question requests a response based on a specific edition, all answers are based on the latest edition of NFPA 70® National Electrical Code®.

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