The 2020 edition of the National Electrical Code, issued Aug. 5, 2019, became effective Aug. 25, 2019, and superseded all 54 previous editions beginning in 1897.

There were a total of 3,730 public inputs with 1,400 first revisions and five first Correlating Committee revisions to the first draft of the 2020 edition. Almost 2,000 public comments resulted in 635 second revisions and 73 second Correlating Committee revisions to the second draft.

All these proposed revisions were open to challenge at the June NFPA Conference and Exposition Technical meeting in San Antonio. Additional challenges were possible at the NFPA Standards Council Meeting in August at NFPA headquarters in Quincy, Mass.

Four new articles were added by the 18 Code -making panels (CMPs); a variety of Code-wide changes were made. NEC CMP 10 added new Article 242 dealing with overvoltage protection; it replaces previous Article 280 for surge protective devices and Article 285 for surge arrestors at over 1,000 volts (V). This new article provides general, installation and connection requirements for overvoltage protection and overvoltage protection devices. Part I deals with general requirements, Part II with surge protection devices and Part III deals with surge arrestors greater than 1,000V.

CMP 6 added two new articles by splitting the medium-voltage requirements in Article 310 into a new Article 311 that covers the use, installation, construction and ampacities for medium-voltage conductors and cables. Existing Article 310 has been extensively revised to improve usability.

Existing Article 328 was removed by incorporating the information into new Article 311. CMP 6 also added a new Article 337 for Type P cable covering general and installation requirements and construction specifications of armored and unarmored Type P cable.

CMP 16 has renumbered old Article 800 to new Article 805 for communications circuits and established a new Article 800, which covers common installation requirements of other articles in Chapter 8, unless modified by others. New Article 800 applies to Article 810 for radio and television equipment, Article 820 for community antenna television and radio distribution, Article 830 for network-powered broadband communications systems and Article 840 for premises-powered broadband communications systems. This change should make Chapter 8, dealing with communications systems, much easier to use.

One Code -wide difference is the change from “short-circuit current” and “available short-circuit current” to the new phrase “available fault current” that is referenced throughout the NEC to provide consistency. “Available fault current” is the phrase used to describe large amounts of current capable of being delivered at a point in the system during a short-circuit condition. The Correlating Committee usability task group studied this issue to make the NEC more user-friendly. The usability task group suggested adding one of two statements in the definition section. The first statement is “the definitions in this section shall apply only within this article;” the second statement is “the definitions in this section shall apply within this article and throughout the Code.” The usability task group advised the panels to use both or either as it may apply.

In the past, the NEC style manual and the introduction to Article 100 implied that any definition that was used in more than one article must be located here. Some articles, such as Article 760 for fire alarm system wiring and Article 725 for remote-control, signaling and power-limited circuits, contain definitions that are commonly used throughout the NEC . However, many definitions are used by people outside the electrical industry and should remain in these articles for ease of use for people not familiar with the NEC . The purpose of these new statements is to clarify the use of these definitions without having to find them in Article 100.