TL;DR
Black iron pipe is the uncoated steel piping with threaded fittings that has long been the default for natural gas and propane distribution inside buildings, named for the dark iron-oxide mill finish that distinguishes it from zinc-coated galvanized pipe. It is strong, heat-resistant, and cheap, assembled with tapered threads sealed by gas-rated dope or yellow PTFE tape.
What it means
Black iron pipe is the uncoated steel piping with threaded fittings that has long been the default for natural gas and propane distribution inside buildings, named for the dark iron-oxide mill finish that distinguishes it from zinc-coated galvanized pipe. It is strong, heat-resistant, and cheap, assembled with tapered threads sealed by gas-rated dope or yellow PTFE tape. The bare steel rusts in wet or buried service, so codes route those situations to coated or plastic alternatives, and exterior runs need paint. Sizing follows the fuel gas code's capacity tables by length and BTU load, and a finished system must hold a pressure test witnessed by the inspector.
Where it sits in the glossary
Black iron pipe 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.
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