Quick Hits

EPISODE 3 — Clearances, Vegetation and Extra-High Voltage — Part I Finale (268.9, 268.10, 268.15)

Slide 1 — Hook "Wrapping up Part I — clearance rules, why trees don't count as support structures, and the special rule above 35,000V."

Slide 2 — 268.9 & 268.10

• 268.9: Clearances for service conductors follow 267.19 (the outside branch circuits/feeders article's clearance rules) — this article doesn't duplicate them, it just points there.

• 268.10: Vegetation (trees, etc.) can NEVER be used to support overhead service conductors or service equipment — trees move, grow, and aren't reliable structural supports.

Slide 3 — 268.15 Over 35,000 volts

• If conductors entering a building exceed 35,000V between conductors, they must terminate in a switchgear compartment or a vault meeting the construction requirements of 450.41-450.48 — this extra containment is required because of the serious arc-flash/insulation-failure risk at that voltage class.

Slide 4 — Quiz + CTA Q: "Can a tree be used to help support overhead service conductors?" A) Yes, if it's healthy and mature B) No — vegetation can never be used for support C) Only for temporary services D) Only if reinforced with cable ties

✅ Answer: B — 268.10 flatly prohibits vegetation as a support method.

CTA: Follow for more daily quick-hit study notes 📚⚡ — Part I complete! Part II (Overhead Service Conductors) is next.

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