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I just learned the National Electrical Safety Code (NESC) excludes utility poles with heights above ground of 60 ft or less from the extreme wind loading design requirements. Is this exclusion supported by data? If not, what will it take to change? This may be a case of commercial considerations overriding good design practice. In that case, those pushing the exclusion should test drive an extended period without power to see if the exclusion really makes sense. I

Extreme wind loading is covered by Rule 250C in the NESC. Per the 2023 NESC Handbook:  Rule 250C was added in 1977 and recognizes that tall structures may be subjected to wind only loadings that exceed the combined ice and wind loadings included in Rule 250B. ASCE Manual 52, Guide for Design of Steel Transmission Towers, was one of the references used in this change. This change was made to specifically recognize that the heavy- and medium-loading conditions of Rule 250B do not properly reflect the actual loads applied by wind to structures higher than 18.3 m (60 ft) that carry conductors of 2 cm (0.8 in.) diameter or greater. There are additional details in the handbook as well.

For more information on the NESC, which is an IEEE publication, see the links below on how to participate and submit change requests.

• NESC Program Page
• 2028 NESC Change Proposal and Revision Schedule

I just learned the National Electrical Safety Code (NESC) excludes utility poles with heights above ground of 60 ft or less from the extreme wind loading design requirements. Is this exclusion supported by data? If not, what will it take to change? This may be a case of commercial considerations overriding good design practice. In that case, those pushing the exclusion should test drive an extended period without power to see if the exclusion really makes sense. I