TL;DR
A reduced pressure zone assembly is the highest grade of backflow preventer, using two independent check valves with a hydraulically operated relief valve between them that dumps water out a vent if either check leaks. Plumbing codes require it where a cross-connection could carry health hazards—irrigation with chemical injection, boilers with treatment, fire lines, commercial services.
What it means
A reduced pressure zone assembly is the highest grade of backflow preventer, using two independent check valves with a hydraulically operated relief valve between them that dumps water out a vent if either check leaks. Plumbing codes require it where a cross-connection could carry health hazards—irrigation with chemical injection, boilers with treatment, fire lines, commercial services. Most jurisdictions mandate testing by a certified tester at installation and annually, with results filed with the water purveyor.
Where it sits in the glossary
Reduced pressure zone assembly 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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