Bonding Backbone Conductor extends through building connecting which components?

• A. Extends through building connecting SBB to PBB
• B. Connects IPBB to ground
• C. Bonds to detachable doors
• D. Bonds to stainless steel hardware

Answer: (A)

Continuous equipotential bonding across the building is the main idea here. The Bonding Backbone Conductor is used to create a single, low-impedance bonding path that runs through the building from the Service Bonding Backbone (SBB) at the service entry to the Panel Bonding Backbone (PBB) at the distribution end. By extending through the structure, it ensures that all metallic enclosures, racks, frames, and bonded points share the same electrical potential, which helps keep fault currents contained, reduces shock risk, and preserves the effectiveness of the bonding system throughout the site. This is why extending through the building to connect SBB and PBB best captures the intended function.

The other scenarios don’t establish that continuous path across the building. Connecting IPBB to ground describes a different bonding relationship focused on a single point rather than a through-building, detachable-door bonding would only address localized points, and bonding to stainless steel hardware centers on specific components rather than creating a complete building-wide bonding backbone.