Services, Grounding & BondingQuestion 48 of 120
A metal underground water pipe qualifies as a grounding electrode only if it is in direct contact with the earth for at least what length?
a.20 feet
b.10 feet
c.8 feet
d.5 feet
Explanation
The metal underground water pipe electrode must have 10 feet or more in direct contact with the earth, including any metal well casing bonded to it. The 20-foot value belongs to the concrete-encased electrode, and 5 or 8 feet do not meet the requirement.
Law Reference: 2023 NEC §250.52(A)(1)Practice all 120 questions free — no signup required.
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