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

Electrical Installation Requirements, Overcurrent Protection, Grounding, and Transformers and Their Vaults

CODE CITATIONS Article 110—Requirements for Electrical Installations Article 240—Overcurrent Protection Article 250—Grounding Article 450—Transformers and Transformer Vaults Working space around electrical equipment

Wiring in Ducts, Plenums, and Other Air-handling Spaces

Navigating the requirements in the National Electrical Code (NEC) for ducts, plenums, and other air-handling spaces can be difficult.

Testing and Maintaining Life Safety Systems

Most electrical contracting firms are involved in installing life safety systems for new building construction and the renovation and expansion of existing buildings, but not in the ongoing system inspection, testing, maintenance, and upgrade.

The Code In Focus--Article 210 - Branch Circuits

210-5 Identification for Branch Circuits

Code Changes Require Technical Substantiation

Sometimes a code change is made with no supporting comment—no technical support —other than “we have been doing it this way for years and have had no trouble.” Section 4-3.3(d) of the NFPA Requirements Governing Committee Projects requires that substantiation be provided for each proposal.

Conduits Entering the Bottom of a Switchboard, Connecting Electric Drive Fire Pumps, and More

CODE CITATIONS Article 110—Requirements for Electrical Installations Article 240—Overcurrent Protection Article 250—Grounding Article 300—Wiring Methods Article 384—Switchboards and Panelboards Article 422—Appliances

Structured Wiring Systems - A New Concept or a Reincarnation?

Recently, a new term has evolved to describe an integration of all low-voltage systems, such as TV, radio, telephone, and Internet/computer interlinks from one main distribution hub to serve all rooms within a building with multifunction communications capability.