TL;DR
A ball valve is a quarter-turn shutoff in which a drilled sphere rotates inside the body: bore aligned with the pipe gives full flow, a 90-degree turn seals it completely. The lever position doubles as an indicator, parallel for open, crossed for closed, and the design seals reliably after years of disuse, which is why plumbers have replaced multi-turn gate valves with these for main shutoffs, water heater isolation, and hose bibb supplies.
What it means
A ball valve is a quarter-turn shutoff in which a drilled sphere rotates inside the body: bore aligned with the pipe gives full flow, a 90-degree turn seals it completely. The lever position doubles as an indicator, parallel for open, crossed for closed, and the design seals reliably after years of disuse, which is why plumbers have replaced multi-turn gate valves with these for main shutoffs, water heater isolation, and hose bibb supplies. Full-port versions match the pipe's inner diameter for unrestricted flow. Codes accept them broadly, and brass bodies for potable water must be lead-free per the Safe Drinking Water Act.
Where it sits in the glossary
Ball valve 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.
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See also
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