TL;DR
An antioxidant compound is the gray joint paste brushed onto aluminum conductors before termination to break up and block the oxide film that makes aluminum connections resistive and hot. Products like Noalox or Penetrox fill the microscopic surface with suspended zinc particles so current flows metal to metal.
What it means
An antioxidant compound is the gray joint paste brushed onto aluminum conductors before termination to break up and block the oxide film that makes aluminum connections resistive and hot. Products like Noalox or Penetrox fill the microscopic surface with suspended zinc particles so current flows metal to metal. It is standard on aluminum service-entrance and feeder lugs, and most lug manufacturers' instructions, enforceable under NEC 110.3(B), call for it. Electricians also apply it when pigtailing old aluminum branch wiring with approved connectors.
Where it sits in the glossary
Antioxidant compound is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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