The National Electric Code (NEC) is part of the National Fire Protection Association’s (NFPA) codes and standards. NFPA code 70, which all 50 U.S. states have adopted, is the standard for safe electrical design, installation and inspection. At the time of publication, the latest edition is the 2014 NEC. The NFPA will release the next edition in 2017. The NEC is available to view online free of charge, as are all NFPA codes. Physical and electronic versions of the NEC, such of PDFs and eBooks, are available for purchase to optimize electronic workflow for electricians. By being familiar with the latest NEC updates and putting this knowledge into practice, you’ll ensure your clients’ safety by reducing the risk of electrical-related accidents and fire hazards.

History of the NEC

The NFPA first published the NEC in 1897. Since then, the U.S. has used the NEC as its singular code for safe electrical designs, installations and inspections. While the code is nationally adopted, it is not a federal law. States and municipalities may amend, alter or reject guidelines and replace them with regulations that local governing bodies deem more regionally acceptable.

The hazards that electrical work may pose, including losses of life or property, motivate municipalities to adopt and enforce building codes that specify best practices and standards for electrical systems. This adoption of standards led to the NEC becoming the de facto set of electrical requirements, as the American National Standards Institute approved the NEC as a national standard.

Since the creation of the NEC, the NFPA developed a Deactivation and Decommissioning (D&D) extension of the code to address the unique situations that the U.S. Department of Energy faces during deactivation and decommissioning projects. The NEC also includes guidance regarding hazardous locations (HAZLOC) as they relate to the U.S. Occupational Safety and Health Administration’s (OSHA) standards.

For each three-year NEC code cycle update, professionals in the NEC’s code-making panel (CMP) determine which codes to update, add and delete. You can find this list in the NEC’s “Committee” section, toward the beginning of the handbook. See if you can get your CMP heroes’ autographs in your copy of the NEC book! If you do, your peers will have nothing but respect and envy for you, and they’ll covet your handbook.

NEC Structure

The NEC includes an introduction, nine chapters, nine annexes and an index. The first four chapters discuss definitions and rules regarding:

  • Wiring materials and methods
  • Installations
  • Circuits
  • Circuit protections
  • General equipments, such as receptacles and switches

The fifth through seventh chapters discuss special occupancy conditions and equipment. The eighth chapter reviews requirements for communication systems. Chapter nine includes tables related to cable, conductor and conduit properties.

NEC Scope

At the time of publication, the NEC covers:

  • The installation of electrical conductors, equipment and raceways
  • Signaling and communications conductors, equipment and raceways
  • Fiber optic cables and raceways for various applications, such as homes, buildings, lots and other structures

The NEC does not cover information related to aircraft, vehicles, underground mines, ships, railways installations for power generation or transmissions, communications equipment under the control of communications utilities, and installations under the control of electrical utilities.

In 2014, the NEC updated codes related to:

  • The accessibility of GFCI outlets
  • GFCI protection for bathrooms, garages, laundry rooms and kitchens
  • AFCI protection, modifications and extensions
  • Electrical vehicle charging equipment and load calculations
  • Heavy duty covers at wet locations
  • Maximum voltage thresholds
  • Selective coordination
  • Available fault currents
  • Grouping multiple currents
  • Identification of underground conductors

Keep in mind that these are just a handful of the hundreds of updates listed in the NEC. It is best to refer to the NEC to learn about the latest codes for your specific application or project.


Learning the NEC is a vital component to obtaining an electrical license. In some states, NEC training in-person or online counts toward state electrical licensing renewals. The following NAC-related resources will aid you with your professional education: