Codes & Standards

 

Essential to the work of the electrical contractor is knowledge of the National Electrical Code, the National Electrical Installation Standards and additional standards and codes administered by the National Fire Protection Association, the Occupational Safety and Health Administration and others. Here is a list of all our articles on codes and standards listed chronologically by issue date. 

Jim Dollard has an extensive background in codes and standards. If you have a query about the National Electrical Code (NEC), Jim will help you solve it. Questions can be sent to codefaqs@gmail.com. Answers are based on the 2014 NEC.
 Previous use of gray conductors


Article 310 in the National Electrical Code (NEC) covers general requirements for conductors and their type designations, insulations, markings, mechanical strengths, ampacity ratings and uses.

A recent change in the 2014 National Electrical Code (NEC) creates a new method for determining the size of service and feeder conductors for 120/240-volt (V), single-phase services for one-family, individual units of two-family dwellings, and individual units for multifamily dwellings.

The 2014 National Electrical Code (NEC) has new requirements for field-applied hazard warning markings, signs and labels. Throughout the NEC, rules that required signs, labels and other markings also required a specific signal word be included in the sign, label or marking.

More on Codes & Standards

 
Code Comments/Why Change a Good Thing?
by Staff |

Prior to and including the 1956 National Electrical Code (NEC) there was a limit of nine conductors in a raceway, except when used for control, stage lighting, elevators, and similar uses.

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Installation of Nonmetallic Sheathed Cable, Exposed or in a Raceway
by Staff |

Is it acceptable to install nonmetallic sheathed cable (NM) exposed on a wall or in an attic, a basement, or a residential garage? Where would physical protection of the NM cable be required, and where is physical protection of NM cable often used but not necessarily required?

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Properly Installing Nonmetallic Cable-Part II
by Staff |

The number and the content of "Code Question of the Day" submissions concerning the installation of nonmetallic sheathed cable suggests vast differences among, or lack of proper inspection of, electrical installations using Type NM cable as the wiring method.

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Branch Circuit, Feeder, and Service Calculations, Motors and Their Circuits and More
by Staff |

CODE CITATIONS: Article 110-Requirements for Electrical Installations; Article 210-Branch Circuits; Article 220-Branch Circuit, Feeder, and Service Calculations; Article 230-Services; Article 250-Grounding; Article 310--Conductors for General Wiring; Article 430-Motors, Motor Circuits, and Controlle

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Confusion with On-site Generators
by Staff |

Two similar installations have been proposed recently. The first is a proposed large hotel on a mountaintop at a distance of several miles from the nearest utility distribution line, and in a location subject to frequent lightning storms.

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Clarifying the Fuzziness Surrounding 'Qualified Person' Language Requires Careful Examination
by Staff |

"In industrial establishments where the conditions of maintenance and supervision ensure that only qualified persons will service the installation..." Think about how many times the National Electrical Code (NEC) begins a requirement with these words.

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