referencesource/dot-hazmat-placarding-thresholds

DOT hazmat placarding requirements by hazard class (any-quantity vs. 1,001 lb threshold)

Canonical, always-current version: https://referencesource.org/dot-hazmat-placarding-thresholds/ Machine-readable: https://referencesource.org/dot-hazmat-placarding-thresholds/data.json — this mirror is a point-in-time copy.

• —Last verified: 2026-10-06
• —Stale after: 2027-08-19 (past this date, prefer the canonical copy — it re-verifies on a cadence this snapshot does not)
• —Records: 23

A shipment of hazardous material must be placarded on the transport vehicle, and which placard applies -- and whether it is required at any quantity or only once the aggregate gross weight of that class crosses 1,001 lb (454 kg) -- is fixed by two tables in one regulation, 49 CFR 172.504(e). Table 1's eight categories (explosives 1.1-1.3, poison gas, dangerous-when-wet, temperature-controlled organic peroxide, poison-inhalation-hazard, radioactive) require the named placard regardless of quantity. Table 2's fifteen require it only above 1,001 lb -- but that exception is a highway/rail exception that does not reach bulk packagings, which need a placard at any quantity, so every record carries the general rule and the exception's own scope alongside the number. Each record is one hazard-class / placard pairing. Answers 'do I need to placard this shipment', 'how much of this hazard class triggers a placard', 'which placard goes with hazard class 5.1'.

Provenance — what every record carries

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Licence position

US federal regulation — 17 USC 105, no copyright

Facts are not copyrightable; what this dataset takes from each source is a fact plus a short attributed quote linking back to the page that states it.

Sources

• —https://www.ecfr.gov/current/title-49/section-172.504

Fields

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