TL;DR
Indirect waste is drainage that reaches the sanitary system only after crossing an air gap or air break into a receptor such as a floor sink, standpipe, or service sink, never by direct pipe connection. Plumbing codes require it for equipment that touches food, drinking water, or sterile goods, ice machines, dishwashers, food prep sinks, water softeners, so a sewage backup can never siphon into them.
What it means
Indirect waste is drainage that reaches the sanitary system only after crossing an air gap or air break into a receptor such as a floor sink, standpipe, or service sink, never by direct pipe connection. Plumbing codes require it for equipment that touches food, drinking water, or sterile goods, ice machines, dishwashers, food prep sinks, water softeners, so a sewage backup can never siphon into them. The visible gap, typically twice the drain pipe diameter, is exactly what the health inspector looks for behind a commercial ice bin.
Where it sits in the glossary
Indirect waste 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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