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. 

The National Electrical Code (NEC) uses the word “harmonic” exactly 11 times, all in combination with or explanation of neutral conductors. However, “harmonic” is not defined in the NEC.

Does the National Electrical Code (NEC) address conductor-withstand ratings for wire-type equipment grounding conductors (EGCs)? Yes, but it is worthy of a more detailed explanation.

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 Answers are based on the 2014 NEC.
 Grounded conductor 
terminations, panelboards

Conductor identification requirements are located in articles throughout the National Electrical Code (NEC). The first such requirement is in Article 110, and it pertains to a specific type of electrical system.

More on Codes & Standards

Assembly Occupancies, Overcurrent Protection and More

Electric service for grounding-electrode conductors Q: The electric utility in our area requires the installation of a ground rod and grounding-electrode conductor in the meter socket. Is it acceptable to ground the grounded-circuit conductor (neutral) in the service-disconnect enclosure?

Branch-Circuit, Feeder and Service Calculations

220.1 Scope Understanding how to perform load calculations is an important part of an electrician’s professional career. Before obtaining a permit, some jurisdictions require paperwork showing load calculations for services and feeders.

AC and MC Bushings, Outdoor Receptacles and More

AC and MC bushings Q: Sections 320.17 and 330.17 indicate that Types AC and MC cables must be installed in accordance with 300.4, which includes protection of the cables by listed bushings or listed grommets that cover all metal edges of metal studs.

Pull- and Junction-Box Calculations, Part VIII

314.28 Pull and Junction Boxes Requirements pertaining to the installation and use of all boxes and conduit bodies used as outlet, device, junction or pull boxes are in Article 314 of the National Electrical Code (NEC).

Only Temporary

Recent discussions on ground-fault circuit interrupter (GFCI) protection for personnel on construction sites have indicated that there seems to be a misunderstanding of whether generator power is excluded from the GFCI requirement.

Transformer Sizes, Metal Clad Cables and More

Outside feeder grounding and bonding Q: What grounding and bonding requirements apply to an outside feeder that supplies a woodworking hobby shop that is located in a detached building and is about 60 feet from, and supplied from, a single-family residence?

Pull- and Junction-Box Calculations, Part VII

314.28 Pull and Junction Boxes Chapter 3 of the National Electrical Code (NEC) covers wiring methods and materials. Article 314 covers the installation and use of all boxes and conduit bodies used as outlet, device, junction or pull boxes, depending on their use.