Panelboards installed in Healthcare facilities and serving the same individual patient vicinity must be bonded together with copper conductors not smaller than which size?

• A. No 12 AWG
• B. No 10 AWG
• C. No 8 AWG
• D. No 6 AWG

Answer: (B)

In healthcare facilities, when multiple panelboards serve the same patient vicinity, they must be bonded together with a copper conductor to create a continuous and low-impedance equipment grounding path. This bond helps ensure that if a fault occurs, the fault current has a reliable path back to the source, allowing the overcurrent protection to operate quickly and keeping exposed metal parts at a safe potential around the patient.

The required minimum size for that interconnecting bonding conductor is copper No. 10. This size strikes a balance between providing a path with sufficiently low impedance to carry fault current and being practical in terms of cost and ease of installation. Using a smaller conductor would raise the impedance of the bonding path, potentially delaying fault clearance and increasing risk to patients and staff. Larger sizes, while acceptable, are not necessary for this particular bonding requirement and add unnecessary expense.

So, the interpanelboard bond for the same patient vicinity must be at least No. 10 copper.