TL;DR
Category 3 water is grossly contaminated water containing pathogens or toxins, the most hazardous IICRC S500 class, covering sewage backups, toilet overflows with feces, flooding from rivers and storm surge, and any water that has seeped through soil or sat contaminated long enough to breed heavy microbial growth. The protocol is removal, not salvage: drywall, insulation, carpet, pad, and other porous materials it touched are cut out and discarded, structural surfaces are cleaned and disinfected, and workers operate in full PPE with containment.
What it means
Category 3 water is grossly contaminated water containing pathogens or toxins, the most hazardous IICRC S500 class, covering sewage backups, toilet overflows with feces, flooding from rivers and storm surge, and any water that has seeped through soil or sat contaminated long enough to breed heavy microbial growth. The protocol is removal, not salvage: drywall, insulation, carpet, pad, and other porous materials it touched are cut out and discarded, structural surfaces are cleaned and disinfected, and workers operate in full PPE with containment. Clearance often involves post-remediation verification before rebuild.
Where it sits in the glossary
Category 3 water 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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