National Electrical Installation Standards

Standards as High as Your Own

The National Electrical Code is the bedrock of the electrical construction business.

Do you know all the ins and outs of the Code? NECA and Electrical Contractor magazine are pleased to present their daily online feature, “Code Question of the Day.”


  • ?
    Friday, February 24, 2017

    Question:

    Can a electrical panel be inside a closet which resides inside of a bathroom? A closet giving more than 30"x36" of working room

    Jake Fascendini

  • ?
    Thursday, February 23, 2017

    Question:

    In the crane world when it comes to exposed bussbar, section 12.3.3 talks about unqualified persons and a limited approach area. When it comes to this, does the 10 ft rule/approach restriction apply to open bussbar for unqualified individuals?

    Derek Johnson

    A

    Answer:

    Hey Derek thanks for your question. Runway contact conductors must be guarded as stated in 610.21 so that people cannot inadvertently touch energized parts. Guarding of live parts 50 volts and higher is covered in 110.27 and elevation is one specific method that is allowed.

    I found Section 12.3.3 in a Reclamation Safety and Health Standard and do not know if that is the specific standard you are referring to but the wording is similar to that in NFPA 70E -2015.

    In general an unqualified person must stay out of the limited approach boundary as stated in 130.4(C)(1) of NFPA 70E. Table 130.4(D)(a) gives a 10 foot limited approach boundary for exposed movable conductors up to 72.5 kV. Superscript note "c" to that table provides some guidance regarding what a movable conductor is. For exposed fixed circuit parts the dimension is 3 ft 6 inches up to 750 volts.

    So if the exposed energized parts are movable, such as crane contact conductors, it would make sense for the employers work practices and procedures to require unqualified persons stay at least 10 feet from the exposed conductors under the conditions stated.

ABOUT CQD: NECA’s Code Question of the Day (CQD) is a leading National Electrical Code® forum for NECA and the industry. The CQD generates a lively dialogue and relative practical and Code-based responses to an ever-increasing and interactive audience.

IMPORTANT NOTICE: All answers are based on the latest edition of the National Electrical Code®, unless the question requests a response based on a specific edition. This correspondence is not a formal interpretation of the NEC®. Any responses expressed to the questions are opinions and do not necessarily represent the official position of NECA, NFPA, or any technical committee. In addition, this correspondence is neither intended, nor should it be relied upon, to provide professional consultation or services.

ABOUT CHARLIE: 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. Charlie was also a member of NECA’s Academy of Electrical Contracting. Charlie’s experienced team of industry experts keep the CQD dialogue and discussions active and informative in the spirit of the man himself, as he wanted.

NECA STANDARDS: NECA publishes the National Electrical Installation Standards™ (NEIS™), a series of ANSI-approved performance and quality standards for electrical construction. Visit NECA-NEIS.org for more information. NEISÔ can be purchased in three formats: as paper books, on CD, or as electronic downloads.

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