For grounding electrode conductors, which splicing methods are permitted?

• A. Irreversible compression or exothermic welding
• B. Soldered joints only
• C. Twist-on connectors only
• D. Crimp connectors with no heat

Answer: (A)

Grounding electrode conductor splices must be permanent, low-resistance bonds that hold up in moisture, soil, and temperature changes. The only methods that meet that requirement are irreversible compression connections and exothermic welding. Irreversible compression creates a deformation that cannot be undone, producing a solid metal-to-metal bond with good mechanical strength and corrosion resistance. Exothermic welding fuses the conductors into one continuous piece, eliminating the metal-to-air interface and remaining dependable even with dissimilar metals or harsh environments.

Soldered joints aren’t considered reliable for grounding splices because they can crack or creep with thermal cycling and moisture, compromising conductivity over time. Twist-on connectors can loosen or corrode in the field, especially underground, leading to high resistance or open circuits. Crimp connectors described as “with no heat” aren’t guaranteed to meet the permanent, corrosion-resistant bond required for a grounding electrode splice.