Hazmat UN Number Lookup

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🏷️ Primary Hazard Class Filter

UN1841

Acetaldehyde ammonia

Miscellaneous Dangerous Goods

Class 9PG III

CAS Registry7664-41-7

Hazchem / EAC2Z

ERG Guide Number171

49 CFR Placards & Labels

MiscellaneousClass 9

⇩ SVG

Reportable Quantity — 1,000 lb (454 kg)

Any release meeting or exceeding this amount must be reported to the National Response Center at 1-800-424-8802 under 40 CFR 302.6 and 49 CFR 171.15.

Not listed as a Marine Pollutant under §172.101 Appendix B.

Regulatory Facts

Packing Group

III

Symbols (col 1)

Labels (col 6)

PIH Zone

—

Packaging references (49 CFR §173.xxx)

Exceptions (col 8A)

§173.155

Non-Bulk (col 8B)

§173.204

Bulk (col 8C)

§173.240

Aircraft quantity limits (col 9)

Passenger / Rail (9A)

200 kg

Cargo Aircraft Only (9B)

200 kg

Vessel stowage (col 10)

Location (10A)

Other codes (10B)

Special provisions (col 7 — §172.102)

IB8 IP3 IP7 T1 TP33

Hazard Classification & Risks

Class 9 — Miscellaneous dangerous goods that present a transport hazard not covered by other classes (e.g. elevated-temperature, environmentally hazardous, lithium batteries) (49 CFR §173.140). Packing Group III — minor danger.

Transport Regulations

Hazard class 9, Packing Group III. Placard/label codes: 9. Special provisions: IB8, IP3, IP7, T1, TP33. Packaging (49 CFR §173): exceptions §155, non-bulk §204, bulk §240. Quantity limits: passenger aircraft/rail 200 kg, cargo aircraft only 200 kg. Vessel stowage: A (other: 34). Classified per 49 CFR §172.101.

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Source & sourcing note

Regulatory data mirrors the U.S. 49 CFR §172.101 Hazardous Materials Table and companion columns (packaging, quantity limits, vessel stowage, special provisions) as published by the U.S. Pipeline and Hazardous Materials Safety Administration (PHMSA).

Emergency-response content is drawn from the 2024 Emergency Response Guidebook (ERG), a joint publication of PHMSA, Transport Canada, and Mexico’s SCT.

The U.S. edition of the ERG and all U.S. federal regulations are public-domain works under 17 U.S.C. §105. Descriptions on this page are plain-English paraphrases; for any compliance decision, consult the authoritative text on eCFR Title 49 and the ERG at PHMSA.dot.gov. “ERG™” is attributed to PHMSA / Transport Canada / SCT and used nominatively.

Regulatory Facts

Packing Group

III

Symbols (col 1)

Labels (col 6)

PIH Zone

—

Packaging references (49 CFR §173.xxx)

Exceptions (col 8A)

§173.155

Non-Bulk (col 8B)

§173.204

Bulk (col 8C)

§173.240

Aircraft quantity limits (col 9)

Passenger / Rail (9A)

200 kg

Cargo Aircraft Only (9B)

200 kg

Vessel stowage (col 10)

Location (10A)

Other codes (10B)

Special provisions (col 7 — §172.102)

IB8 IP3 IP7 T1 TP33

Source & sourcing note

Emergency-response content is drawn from the 2024 Emergency Response Guidebook (ERG), a joint publication of PHMSA, Transport Canada, and Mexico’s SCT.