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Understand the critical difference between grounding and bonding. Learn how grounding protects equipment from voltage surges while bonding protects people by clearing ground faults through low-resistance return paths.

Show Notes (Full):
Episode Overview
Grounding and bonding are often confused but serve distinct safety functions. This episode clarifies these critical concepts and explains why proper installation is essential for electrical safety in every home.

What You'll Learn
Understanding the Difference:

• Grounding protects electrical equipment (acts like surge suppressor)
• Bonding protects people (clears ground faults safely)
• Why both systems are essential but serve different purposes
• How voltage surges find safe paths to ground
• Why bonding provides low-resistance return paths for fault current

How Bonding Clears Ground Faults:

• What happens when a hot wire contacts metal (the "rat example")
• Why low resistance is critical (high resistance = circuit breaker won't trip)
• How Ohm's Law determines current flow in bonded circuits
• Why loose bonding clamps create deadly hazards
• The myth: electricity doesn't "want" to go to ground—it returns to its source

Grounding Electrode System Components:

• Grounding electrodes: rebar, rods, pipes, metal water service
• Grounding electrode conductor (GEC) sizing and installation
• Where the GEC connects (between service drop and service equipment)
• Why multiple grounding connections downstream are prohibited
• Ufer grounds and concrete-encased electrodes

Bonding Requirements:

• Metal water and gas distribution pipes
• Electrical conduit, equipment cabinets, and cases
• HVAC ducts and metal framing
• CSST gas tubing (special bonding requirements)
• Satellite and cable TV coax
• Bonding jumpers around interruptions (water meters, plastic components)

Equipment Grounding Conductors (EGCs):

• EGCs are really bonding wires, not part of grounding system
• Provide low-resistance return path for equipment that may become energized
• Found in modern electrical cable since approximately 1960

Typical Defects to Report

• Damaged, loose, or undersized GEC (#8 min for <150A, #6 min for ≥150A)
• Absent or loose grounding/bonding clamps
• Clamps on corroded, painted, or contaminated surfaces
• Improperly spliced GEC (must use listed compression connector or welding)
• Metallic conduit with plastic fittings (bonding path interrupted)
• Underground water pipe GEC connection >5 feet from entry point
• Missing bonding jumpers around water meters and removable components
• CSST gas tubing not bonded properly

Key Takeaways

• Grounding limits voltage surges; bonding clears ground faults
• Low resistance bonding paths are essential for safety
• All accessible grounding electrodes must be bonded together
• Metal that could carry electricity must be intentionally connected
• GEC connection occurs only once—at or before service equipment

Critical Safety Principle

"If it is metal and it is or could be near electrical wires, then it probably needs to be bonded to the grounded wire of the utility."

IRC Code References
IRC 2018: E3607, E3608, E3609, E3610, E3611, G2411

Study Tips

• Focus on

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