About this episode
⚡ I WARNED NEC CODE-MAKING PANEL 5. MORE THAN TWO YEARS LATER, NFPA RESEARCH SUPPORTS MY CONCERNS!
During the development of the 2026 National Electrical Code, I raised serious technical concerns with CMP-5 regarding equipment grounding conductor (EGC) sizing, particularly the language allowing an EGC to be no larger than the ungrounded circuit conductors, despite the OCPD-based sizing requirements of Table 250.122.
I publicly documented these concerns on January 31, 2024.
Fast-forward to October 9, 2026.
The NFPA Fire Protection Research Foundation published its study, Sizing of Equipment Grounding Conductors – Literature Review.
HERE IS WHAT NFPA STATES:
«”The sizing of conductors intended to carry ground fault current, including supply side bonding jumpers, grounded circuit conductors (neutral) and equipment grounding conductors is inconsistent.”»
The research also acknowledges that the historical technical basis for EGC sizing requirements, including parallel installations, remains relatively unclear.
THIS IS EXACTLY WHY I RAISED THE ISSUE!
My concerns were valid. The fundamental technical questions I challenged are now being formally examined through NFPA-supported research.
The study does not establish that every existing installation is unsafe, but it reinforces something I have argued for years: Code requirements must be supported by sound electrical engineering principles, not simply longstanding assumptions.
An equipment grounding conductor must provide an effective ground-fault current path and facilitate operation of the overcurrent protective device.
If Table 250.122 establishes the minimum EGC size based on the OCPD, why should the size of an ungrounded conductor automatically limit that requirement?
That question deserves a technically substantiated answer.
As a member of NEC CMP-5, I believe challenging existing requirements when their technical basis is uncertain is part of our responsibility to electrical safety.
I raised the concern in 2024. NFPA published its research in 2026. The discussion is far from over.
📖 My original article (January 2024):
📖 NFPA Research (October 2026):
https://www.nfpa.org/en/education-and-research/research/fire-protection-research-foundation/projects-and-reports/equipment-grounding-conductors-sizing-literature-review
Paul W. Abernathy, CMECP®
NEC Code-Making Panel 5
Electrical Code Academy, Inc.
#NEC2026 #NFPA70 #CMP5 #ElectricalSafety #GroundingAndBonding #EquipmentGroundingConductors #ElectricalEngineering #NationalElectricalCode
