Transmission Engineering James Houston Chief Engineer Member of NESC Subcommittee 3

History & Development of the National Electric Safety Code Started in 1913 by the National Bureau of Standards as a circular. Published as various parts until NBS Handbook H30 was published in 1948 which was the last complete edition of the NBS Handbook. Published in parts again until 1970 when the sections which became the NEC and the Radio Installations Rules were split out. Since 1981 has been published periodically in its present form with extensive changes in 81, 87, and 90.

History & Development of the National Electric Safety Code The 1997 code edition was the first to be published for a five year cycle. The current edition is now the 2017. It is available in both printed and electronic form.

What is the Purpose of the NESC? The purpose of these rules is the practical safeguarding of: Public Utility Workers Utility Facilities during the installation, operation, or maintenance of electric supply and communication lines and associated equipment. IT IS NOT TO BE CONSIDERED AS A DESIGN SPECIFICATION OR INSTRUCTION MANUAL.

General Rules for Using the NESC Rule 012. General Rules A. All electric supply and communication lines and equipment shall be designed, constructed, operated, and maintained to meet the requirements of these rules. B. The utilities, authorized contractors, or other entities, as applicable, performing design, construction, operation, or maintenance tasks for electric supply or communication lines or equipment covered by this code shall be responsible for meeting applicable requirements.

Why We Follow the National Electrical Safety Code? The NESC as written is a voluntary standard. However, some editions and some parts of the Code have been adopted, with and without changes, by some state and local jurisdictional authorities. To determine the legal status of the National Electrical Safety Code in any particular state or locality within a state, the authority having jurisdiction should be contacted. Who is the authority having jurisdiction? State Public Service Commissions

NESC Committees S/C 1: Purpose, Scope, Application, Definitions, References S/C 2: Grounding Methods S/C 3: Electric Supply Stations S/C 4: Overhead Lines - Clearances S/C 5: Overhead Lines - Strength & Loading S/C 7: Underground Lines S/C 8: Work Rules Executive Subcommittee Interpretations

Questions?