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 2017 NEC.
 White conductors 
in cable assemblies

For many years, the mystery of area classification has resided with a select group of experts within the electrical, petrochemical and industrial sectors. Many electricians, electrical engineers, fire inspectors and electrical inspectors have remained outside of this group.

In the 2017 National Electrical code (NEC), there are a few changes in 110.26. The first change is in subsection (A), which is part of a global change for the upper voltage threshold.

Before we proceed, in part 3 of this series, the change in Section 230.70(A)(4) dealing with service disconnects on one- and two-family dwellings was reversed during the late stages of the development process and never made it into the 2017 National Electrical Code (NEC).

More on Codes & Standards

Avoiding the Pitfalls

According to the Design-Build Institute of America (DBIA) “Design-Build is a process that has been embraced by the world's great civilizations. In ancient Mesopotamia, the Code of Hammurabi (1,800 BC) fixed absolute accountability upon master builders for both design and construction.

Box-Fill Calculations, Part X

314.16 Number of Conductors in Outlet, Device, and Junction Boxes, and Conduit Bodies The National Electrical Code has specific requirements detailing how to calculate the maximum number of conductors in boxes (outlet, device, junction, etc.) and conduit bodies.

New Method to Protect Circuits

Arc-fault circuit-interrupter(AFCI) protection requirements were first submitted to the National Electrical Code (NEC) process for the 1996 NEC but were not accepted until the 1999 NEC.

Box-Fill Calculations, Part IX

314.16 Number of Conductors in Outlet, Device, and Junction Boxes and Conduit Bodies Section 314.1 covers the scope of Article 314. This article covers the installation and use of all boxes and conduit bodies used as outlet, device, junction or pull boxes, depending on their use.

Safety Horizon: 70E Standard

Twenty-five years ago, the National Fire Protection Association (NFPA) first prepared a set of standards to ensure electrical workers were safe on their jobs. So why has this standard-known as the NFPA 70e-suddenly become such a big deal?

Box-Fill Calculations, Part VIII

Article 314 C Outlet, Device, Pull and Junction Boxes; Conduit Bodies; Fittings; and Manholes 314.16(B) Box-Fill Calculations Article 314 of the National Electrical Code contains requirements pertaining to the installation and use of all boxes and conduit bodies used as outlet, device, junction or

Meter Sockets, Laundry Room Receptacles and More

Article 90 Introduction Article 210 Branch Circuits Article 220 Branch-Circuit, Feeder, and Service Calculations Article 230 Services Article 240 Overcurrent Protection Article 250 Grounding Article 310 Conductors for General Wiring Article 406 Receptacles, Cord Connectors and Attachment Plugs (Cap