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With every release of a new NEC code book, electricians across the country find themselves faced with a large, unwieldy document that has many wide-ranging implications for their industry and their working life. With the current (2020) edition of the NEC code book comprising more than 900 pages, having an accessible guide to the most important changes is critical. In this article, we look at the background and structure of the new code book, some of the main impacts this document will have on master and journeyman electricians alike, and some recommendations for training and retraining key staff on its most important elements.

Background Basics

First published in 1897, the National Electrical Code Book outlines a set of country-wide best practices for the installation and repair of electrical wiring in homes and businesses. The NEC is updated every three years; its most recent iteration was released on August 5, 2019. For working electricians, staying up to date with the latest version of the code is essential; though on its own the NEC is not legally binding, it serves as a de facto guide for state and municipal organizations for the development of regional building codes. Thus, by being aware of the most recent changes to the code, electricians and installers can effectively and legally work almost anywhere in the country.

Structure and Outline

As with all more recent versions, the 2020 NEC code book is broken down into nine chapters:

    • Chapter One provides an overview of the code, featuring concise definitions of any term used in two or more articles. This is followed by a second set of definitions specific to any equipment or installation operating at over 1000 volts, nominal. A new Part III in Article 100 provides those terms and definitions specific to Hazardous (Classified) Locations. The chapter also covers general requirements for the examination and approval, installation and use, access to and spaces about electrical conductors and equipment; enclosures intended for personnel entry; and tunnel installations.
    • Chapter Two covers the wiring and protection of grounded connectors, branch circuits, feeders, service conductors and other devices. This chapter also discusses overcurrent protection, grounding and bonding, and surge protection for devices installed in systems of over as well as under 1000 volts nominal.
    • Chapter Three treats wiring methods in greater detail, outlining a comprehensive set of recommendations for different equipment and materials commonly used in residential, commercial, and other electrical installations, including medium voltage conductors and cable.
    • Chapter Four covers the application and installation requirements for general use equipment including, but not limited to, receptacles and attachment plugs, switches, switchboards, appliances, lighting systems, capacitors, and HVAC units.
    • Chapter Five includes recommendations for electrical equipment and wiring in special occupancies where the building’s intended use will dictate best practices. These include locations such as mobile home parks, temporary structures, health care facilities, and intrinsically safe locations.
    • Chapter Six covers provisions and recommendations for working with special equipment ranging from cranes and hoists to wind and photovoltaic electrical systems.
    • Chapter Seven addresses the safety and wiring considerations of emergency alert systems, legally required standby power systems, fire alarms and other devices essential to emergency preparedness and business continuity..
    • Chapter Eight outlines additional considerations and requirements for working with (non-emergency) communication systems, such as radio and television equipment, broadband networks, antennas and more.
    • Chapter Nine provides a convenient reference of important tables containing nominal dimensions for different wiring types, conduit values and properties, and more, grouped by relevant article.

In addition to the nine main chapters of the 2020 NEC code book, a series of 10 informative annexes is included (Annexes A through J) which contain information beyond the scope of the code itself that working electricians may nonetheless find useful. This includes standards for accessible design, specific product safety standards and more.

Behind the 2020 NEC

Whenever the NEC is revised, there are multiple steps in the process. For the 2020 NEC, there were 3730 public inputs, leading to 1400 first revisions. The first draft was posted in June 2018, and after that, over 1900 public comments related to changes were logged. This led to over 700 additional revisions in the code for the second draft. Then, the new edition of the code was approved and published. There are also changes that happen afterward, called TIA’s (Tentative Interim Amendments) that are also enforceable. Errata, or errors that have been corrected, are published as well.

New Additions

One of the first things anyone will notice upon receiving the 2020 NEC guidebook is the addition of two covered installations and four new articles:

    • Covered Installations: Section 90.2(A) of the 2020 Code has added the two following installations covered:5) Installations supplying shore power to ships and watercraft in marinas and boatyards, including monitoring of leakage current flow (revised Article 555).
      6) Installations used to export electric power from vehicles to premises wiring or for bidirectional current flow (revised Article 625).
    • Article 242: New Article 242 combines and replaces former Articles 280 and 285 and addresses surge protective requirements, devices and arresters. Having both previous NEC articles combined into one and located immediately after Article 240 (Overcurrent Protection) makes sense and improves the overall usability of the NEC. This article provides the general requirements, installation requirements, and connection requirements for overvoltage protection and overvoltage protective devices. Part II covers surge-protective devices (SPDs) permanently installed on premises wiring systems of not more than 1000 volts, nominal, while Part III covers surge arresters permanently installed on premises wiring systems over 1000 volts, nominal.
    • Article 311: Article 328 from the 2017 NEC was deleted, and its contents were relocated to a new Article 311, “Medium Voltage Conductors and Cables.” This new article also incorporates requirements for medium voltage cables and conductors rated over 2,000 volts, which were formally located in Article 310. The scope of Article 310 has been revised and is now limited to not more than 2,000 volts. Requirements and ampacity tables for conductors over 2,000V have been relocated into Article 311. Article 311 includes the installation, construction, and ampacities for medium voltage conductors and cable (Type MV).
    • Article 337: New article 337 covers Type P cable. In the past, Type P cable was allowed in certain applications, but there was no specific article in the NEC for this cable. Type P cable is “a factory assembly of one or more insulated flexible tinned copper conductors, with associated equipment grounding conductor(s), with or without a braided metallic armor and an overall nonmetallic jacket.” The new article covers the use, installation, and construction specifications for this cable which is flexible, rugged, and used in oil and gas well drilling installations or other adverse conditions.
    • Article 800: Article 800 has been introduced to cover general requirements that were previously found in articles 800, 820, 830, and 840. This article replaces redundant requirements found in each of the articles during past code cycles and covers “communications circuits, community antenna television and radio distribution systems, and premises-powered broadband communications systems.” The article clarifies general requirements that can be modified by other articles in Chapter 8 (805, 820, 830, or 840). The article that was previously 800 – Communications Circuits – was moved to become article 805.

Other New Features of the 2020 NEC Code Bookk

While the four new articles in the 2020 NEC are the most noticeable changes, they are not necessarily the ones that will have the most impact on training and compliance over the next three years. The NEC has wide-reaching implications and, as more municipalities adopt its most recent set of standards, it is important to stay aware of any changes that can affect your business. Some of the most important differences between the current NEC and those that came before it include:

    • Exterior Emergency Disconnects: Helps to improve electrical safety for emergency responders at one- and two-family dwelling installations.
    • Deenergizing Panel Boards: Revises service disconnect rules to help increase electrical worker safety.
    • Marinas and Boatyards: Updates ground-fault protection and leakage-current measurement device requirements
    • Power Over Ethernet: Adapts NEC requirements to meet the installation practices of new and evolving technologies.
    • Conducting Load Calculations: Modernizes the tables currently in use for calculations to reflect improvements in energy efficiency.
    • Reorganization of Article 310: Includes new user friendly numbering for important ampacity tables.
    • New General Requirement: Covering cables installed exposed on ceiling surfaces and sidewalls.

The 2020 NEC and Emergency Power Disconnects for Dwellings

This is the new section of the NEC that requires an emergency power disconnect to be installed in a readily accessible location outside of the dwelling. Some parts of the country have been mounting the service disconnect outside for years. In those areas this is not a major adjustment, but it requires that it be marked as both the service disconnect and the emergency disconnect. In other areas where the service disconnect has traditionally been installed inside the home, there are three options for meeting this requirement: mount the service disconnect outside and mark it as mentioned; provide an adequately rated meter disconnect that is marked “emergency disconnect, meter disconnect, not service equipment”; and any other listed disconnect switch that is suitable for use as service equipment is marked “emergency disconnect, not service equipment.”
There was also a revision to add conditions for a service disconnect to consist of two to six switches or circuit breakers. This will force the majority of service disconnecting means to be a single switch or circuit breaker or meet certain requirements in order to have more than one. This came from an input that based the need for this revision on safe electrical work practices. This revision provides the ability for an installer/maintainer to operate a single disconnect that de-energizes conductors and circuit parts in the enclosure except for the line side of the disconnecting means. This is aimed at reducing the likelihood of an incident with energized conductors or circuit parts in the service equipment, and enhancing safety.

Training, Implementation and Electrical NEC Exam Preparation

As these and other contentious issues indicate, there’s no question the 2020 NEC is a complex document. This article covers only a small portion of the most recent changes and their implications for various professionals. Many electricians find that periodic retraining with an accredited continuing education institution is an excellent way to get up to speed quickly and minimize their risk of noncompliance. StateCE’s electrician program makes it possible for an experienced or new electrician to train on code requirements in their spare time, learning from skilled industry experts who understand the latest regulatory changes and can provide insights that will help better implement them in practical situations.
We offer four program streams to meet the needs of every professional, including journeyman electricians, master electricians and journeyman and master sign electricians. All course content is available online, allowing you to train at your own pace from anywhere in the country. Since 2001, our institution has helped more than 100,000 professionals expand their credentials, brush up on the latest requirements or train for a new career. Contact StateCE today for more information about any of our electrician programs.