CGA cylinder valve connection number by gas

Which Compressed Gas Association (CGA) valve outlet/connection number a given gas uses in North America, e.g. 'Acetylene -> CGA 510', 'Oxygen -> CGA 540 (or 296b0)'. Attaching the wrong regulator to the wrong cylinder is a documented cause of fires and explosions, and the CGA numbering exists precisely to make an incorrect connection physically impossible, so the value only holds if it is right. Two independent vendor technical references (Matheson/Nippon Sanso and CONCOA) are read separately, and where both cover the same gas the two answers sit on one page side by side, each with its own chart's quote. That is 24 of the 96 gases here; the other 72 appear on only one of the two charts and carry that chart's answer alone, named as such. The charts do not always agree, which is the point of carrying both: for methyl chloride Matheson prints 660 and CONCOA prints 510, and where the primary number matches the two often list different alternates (argon is '580*/718' on one chart and '580/680/677' on the other). The charts answer two different questions and every record says which one it answers: a pure-gas row gives the fitting for a cylinder of that gas on its own, and a mixed-gas row gives the fitting for that gas as the minor component of a mixture, which is often a different number. CONCOA prints both tables; the Matheson chart is pure gases only. Answers 'what CGA fitting does argon use', 'CGA number for oxygen', and flags where a gas has more than one valid connection (e.g. primary vs UHP/high-purity service).

24 records where two or more sources state different values. Both sides are reproduced on the record page, each with its own source and quote.

The data

Where this came from

Every record above links the page it was taken from and quotes the sentence that states it. These are the 2 sources this dataset was assembled from.

• concoa.comhttps://www.concoa.com/sites/default/files/ADC3010%20AF%20CGA%20selection%20charts.pdf
• us.nipponsanso.comhttps://us.nipponsanso.com/pdfs/gasequipment/CGA-Connection-Chart.pdf

Machine-readable

• data.jsonThe whole dataset — every record with its source URL and source quote.
• Open Knowledge Format bundleOne JSON object per line — every record's frontmatter and quoted span exactly as it is held here, in one fetch.
• data.csvThe same records as one flat table, for a spreadsheet or a dataframe. The last four columns are the source URL, the quoted sentence it was read from, the date we last checked it, and which columns are our reading rather than the page's words.
• How this is made and checkedWhat "verified against source" does and does not mean.

From your own code

Same records, same quotes, without scraping the page: refsource is on PyPI and npm. Each value comes back carrying the URL it was read from and the sentence on that page that states it — .source and .quote sit on the value itself rather than in a side channel, so the checking step is available instead of skipped.

pip install refsource
refsource lookup cga-cylinder-valve-connection-by-gas gas="Nitrogen Dioxide"

npx -y refsource lookup cga-cylinder-valve-connection-by-gas gas="Nitrogen Dioxide"

Set your AI assistant up to use this

Two files and no account. Put this in .mcp.json at the root of your project — Claude Code, Cursor, Windsurf, VS Code and Codex all read that file — and your assistant can look this dataset up instead of recalling it. The server is remote, keyless and read-only.

{
  "mcpServers": {
    "referencesource": {
      "type": "http",
      "url": "https://referencesource.org/mcp"
    }
  }
}

Add to Cursor · or, on the command line: claude mcp add --transport http referencesource https://referencesource.org/mcp --scope project

Then one line in the project's CLAUDE.md or AGENTS.md, so the assistant knows when to reach for it:

When a question needs "CGA cylinder valve connection number by gas", call the referencesource MCP server at https://referencesource.org/mcp (tool `search_records`, dataset_slug `cga-cylinder-valve-connection-by-gas`) instead of answering from memory — every record it returns carries its source URL and a verbatim quote from that page.

What each tool does, and the servers built over single registers: Connect your AI assistant.

117 records. last verified against source 2026-08-28. due for re-check by 2028-08-27.

Licence. Facts extracted from freely published vendor technical references. CGA connection numbers are a safety standard fact, not a copyrightable compilation; no chart is reproduced, only the per-gas number cited with attribution.