The National Electrical Safety Code 2017: Safety in Numbers

The 2017 NESC includes some major updates, as highlighted in this article.


One of the oldest and most ubiquitous safety codes, the National Electrical Safety Code (NESC) is a rich source of safety practices associated with electric supply and communication systems. Every 5 years, NESC users come together and go through a rigorous review to ensure the code stays up-to-date and relevant for the protection of the public, utility workers, and utility facilities.

Many hours were spent revising and updating the code to continue the legacy of providing best practices for safety of electricity supply and communication utility systems to both public and private utilities. The 2017 NESC includes some major updates, as highlighted below and in this infographic:

  • Rules 92C1 & 96C: Exceptions were added to exempt four-grounds-in-each-mile requirement under specific limiting conditions.
  • Rule 110A: Revisions address safety sign locations, adjoining fence restrictions, and impenetrable fence modifications.
  • Rule 124A1: Revised to require Electric Supply Station clearance values in Tables 124-1 and 110-1 to have appropriate atmospheric correction factors applied for altitudes above 1,000 m (3,300 ft).
  • Rule 215C2-C8: Guy insulator rules were rewritten and reorganized to make them easier to understand and apply with the voltage-transfer rules associated with guy insulators being removed.
  • Rule 238C: Now requires a 1.02-m (40-in) vertical clearance between luminaires that are not effectively grounded and communication cables and equipment located in the communication space.
  • Rule 250C: Replaced the reference for extreme wind map from ASCE-7 to ASCE-74.
  • Rule 261H1: Information was added regarding Aeolian vibration and mitigation methods.
  • Rule 354D: Exceptions were added to exempt the number of grounds-in-each-mile requirement under specific limiting conditions.
  • Rule 410A3: Revised to include new requirements and exceptions for protecting workers with arc-related clothing and equipment.
  • Rule 420K: Revised to include new requirements for the use of fall protection equipment.

The 2017 Edition of NESC is available now for presale and will be shipped Aug. 1, 2016.

-Michael Hyland is NESC chair and senior vice president of engineering services at the American Public Power Association (APPA). This article originally appeared on IEEE. IEEE is a CFE Media content partner.

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