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 Answers are based on the 2014 NEC.
 Phase converters and fire-pump service

Article 450 in the National Electrical Code (NEC) covers requirements for transformers. The scope of Article 450, located in 450.1, states that it covers the installation of all transformers, but there are eight exceptions.

NFPA 70, the National Electrical Code (NEC), is an installation code, while NFPA 70E is the Standard for Electrical Safety in the Workplace. There is an unofficial line of demarcation between the two documents.

An electrical contractor recently requested information about the required emergency disconnects for a motor-fuel-dispensing facility.

More on Codes & Standards

Pull- and Junction-Box Calculations, Part IV

314.28 Pull and Junction Boxes The National Electrical Code covers outlet, device, pull and junction boxes; conduit bodies; fittings; and handhole enclosures in Article 314.

Emergency Protection ... Stat!

Providing mechanical protection for branch circuits supplying critical loads in a hospital is extremely important. Any potential damage to these circuits could cost lives.

Panelboards in Stairways, Color Coding and More

Control-circuit transformers Q: Do the requirements of Article 450—Transformers and Transformer Vaults or Article 725—Class 1, Class 2 and Class 3 Remote-Control, Signaling, and Power-Limited Circuits apply to a control-circuit transformers in a 480-volt combination motor starter?

Pull- and Junction-Box Calculations, Part III

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.

Pull- and Junction-Box Calculations, Part II

314.28 Pull and Junction Boxes The National Electrical Code (NEC) has specific requirements detailing how to calculate the maximum numbers of conductors in boxes (outlet, device, junction, pull, etc.) and conduit bodies.

Utility-Interactive PV Systems

A utility-interactive photovoltaic (PV) system is defined in Section 690.2 of the National Electrical Code (NEC) (NFPA 70-2005) as a “photovoltaic system that operates in parallel with and may deliver power to an electrical production and distribution network.” NEC Article 690 covers Solar Photovol

When to Supplement

A new definition covering supplementary overcurrent-protective devices has been added to Article 100 in the 2005 National Electrical Code (NEC) to indicate that limited protection may be provided for specific applications or utilization equipment.