TL;DR
Listing and labeling is the certification system in which a nationally recognized testing laboratory, such as UL or ETL, tests a product against a safety standard and authorizes its mark on the unit. Electrical and mechanical codes require listed equipment installed according to the conditions of its label and instructions, and inspectors will fail unlisted panels, fixtures, or chargers regardless of how well they are wired.
What it means
Listing and labeling is the certification system in which a nationally recognized testing laboratory, such as UL or ETL, tests a product against a safety standard and authorizes its mark on the unit. Electrical and mechanical codes require listed equipment installed according to the conditions of its label and instructions, and inspectors will fail unlisted panels, fixtures, or chargers regardless of how well they are wired. The mark and file number on the nameplate are what the inspector actually checks.
Where it sits in the glossary
Listing and labeling is part of the Certifications 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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