67 records

How often does this cylinder or tank have to be retested?

67 records covering 52 container specifications, one fact each. Every value is transcribed from the source that states it and carries the sentence it was taken from: 5 sources across 2 sites, last checked 2026-09-30, due for re-check by 2027-08-06. Every record is listed below, each linking the page its value came from.

About this data

Mandatory requalification, retest and inspection intervals for pressure containers under 49 CFR Part 180, with the qualifier that decides which interval applies. Each record is one container specification under one test type, stating the interval in years and the condition attached to it. Covers cylinders (49 CFR 180.209), cargo tanks (180.407), intermediate bulk containers (180.352) and portable tanks (180.605). Answers 'how often does a scuba tank need hydro testing', 'DOT 3AL requalification 5 years or 12', 'IBC tote retest interval 2.5 years', 'MC-331 propane cargo tank internal visual inspection frequency', and 'when does a DOT 3AA cylinder qualify for the 10 year star'. The interval is a property of the specification, the service and the configuration together, not of the container alone, and the exceptions are where the answers go wrong: DOT 3AL is 5 or 12 years depending on service, and an MC-331 under 3,500 gallons in dedicated propane service built from non-quenched-and-tempered SA-612 gets 10 years where every other cargo tank gets 5. Past the due date the container may not be filled and offered for transportation.

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 5 sources this dataset was assembled from.

• law.cornell.eduhttps://www.law.cornell.edu/cfr/text/49/180.209
• law.cornell.eduhttps://www.law.cornell.edu/cfr/text/49/180.407
• law.cornell.eduhttps://www.law.cornell.edu/cfr/text/49/180.352
• govinfo.govhttps://www.govinfo.gov/content/pkg/CFR-2025-title49-vol3/xml/CFR-2025-title49-vol3-sec180-209.xml
• law.cornell.eduhttps://www.law.cornell.edu/cfr/text/49/180.605

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 hazmat-container-retest-intervals test_type="Periodic requalification"

npx -y refsource lookup hazmat-container-retest-intervals test_type="Periodic requalification"

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 "How often hazmat cylinders, cargo tanks, IBCs and portable tanks must be retested", call the referencesource MCP server at https://referencesource.org/mcp (tool `search_records`, dataset_slug `hazmat-container-retest-intervals`) 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.

67 records. last verified against source 2026-09-30. due for re-check by 2027-08-06.

Licence. Facts extracted from the US Code of Federal Regulations, a US government work not subject to copyright. Text is read via law.cornell.edu for historical reasons (eCFR used to block our fetcher; retested 2026-09-24 and it no longer does), and via govinfo where Cornell's rendering mangles a typeset fraction; the fact is the regulation's, not the host's, and each record quotes a short verbatim span and links back to the section.