National Electrical Installation Standards

Standards as High as Your Own


The Code Question of the Day (CQD) is NECA and ELECTRICAL CONTRACTOR Magazine’s flagship National Electrical Code (NEC®) public forum for the industry, sponsored by EATON.

The daily distribution of Q&A generates a lively dialogue and shares relative Code-based practical responses.

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    Friday, March 24, 2023


    Good morning and an advanced shout-out thank you for your efforts. NEC® article 300.8 - Installation of Conductors with Other Systems states: Raceways or cable trays containing electrical conductors shall not contain any pipe, tube, or equal for steam, water, air, gas, drainage, or any service other than electrical. If one were to install a cable tray divider, could the cable tray then share electrical conductors with any of the other systems mentioned keeping the conductors on one side of the divider and the other system on the opposite side? I'm thinking probably not but would appreciate another opinion. Thanks in advance, Greg Prudence
  • ?
    Wednesday, March 22, 2023


    Hi Code Friends! Does a #4 Grounding Electrode Conductor require physical protection? Thanks, J.D. Swope


    Hello J.D., thanks for the question. Section 250.64(B)(2) provides guidance on the protection of Grounding Electrode Conductor size #6 AWG and larger. Grounding Electrode Conductors exposed to physical damage require protection by one the of the methods provided in 250.64(B)(2):

    • Rigid Metal Conduit
    • Intermediate Metal Conduit
    • Schedule 80 PVC
    • RTRC-XW
    • EMT
    • Cable Armor 

    When exposure to physical damage is in question, it is always advisable to contact the local AHJ.

ABOUT CQD: The Code Question of the Day (CQD) is NECA and ELECTRICAL CONTRACTOR Magazine’s flagship National Electrical Code (NEC®) public forum for the industry, sponsored by EATON. The daily distribution of Q&A generates a lively dialogue and shares relative Code-based practical responses.

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CHARLIE TROUT: Charles M. Trout, better known as Charlie, was a nationally known NEC® expert and author. He served on several NEC® technical committees and is past chairman of CMP-12. In 2006 Charlie was awarded the prestigious Coggeshall Award for outstanding contributions to the electrical contracting industry, codes and standards development, and technical training. Even though Charlie passed away in October of 2015, his work continues in spirit. NECA continues to maintain this question forum for its many subscribers in memory and recognition of all his significant contributions to making the NEC what it is today.

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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®.

This correspondence is not a formal interpretation of the NEC® and any responses expressed to the questions are opinions and do not necessarily represent the official position of NECA, NFPA, the NEC Correlating Committee any Code-making panel or other electrical technical committee. In addition, this correspondence is neither intended, nor should it be relied upon, to provide professional consultation or services. 

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