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UN identification number

UN1089: Acetaldehyde

UN1089 appears 1 time in the Hazardous Materials Table (49 CFR §172.101). Hazard class 3, packing group I.

ID numberUN1089
Hazard class3
Packing groupI
Label codes3

All §172.101 entries for UN1089

Proper shipping nameClassPGLabels
Acetaldehyde3I3

Open any entry for packaging sections, special provisions, air limits and vessel stowage.

What it means

3
Class 3 — Flammable liquid. Liquids that give off vapors that can ignite — for example gasoline, acetone, and many solvents.

Packing group ranks danger within the class: PG I = great danger.

Label codes (column 6): 3 → Flammable liquid label.

UN numbers are recognized for international and domestic transport.

Reportable quantity (RQ)

  • Acetaldehyde is listed in Appendix A with an RQ of 1000 lb (454 kg).

If a single package contains the RQ or more, the material is also a hazardous substance and “RQ” is added to the shipping description. How RQ is measured →

Example basic description

UN1089, Acetaldehyde, 3, PG I

Proper shipping name shown without the table's italic descriptive text. Order per §172.202: ID number, proper shipping name, hazard class, packing group. Example only — add technical names, “RQ”, quantities and other elements your shipment requires.

What to check next

  1. Match the name. Compare your SDS Section 14 to the proper shipping names above and pick the row with your packing group.
  2. Read the special provisions on the entry page (§172.102) — they can add limits or exceptions.
  3. Check packaging — the entry page lists the Part 173 sections for exceptions, non-bulk and bulk.
  4. Labels & placards. Placarding depends on class and quantity — see Table 1 vs Table 2.
  5. Emergency response. Find the response guide for UN1089 in the current PHMSA Emergency Response Guidebook.
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Common questions about UN1089

What is UN1089?

UN1089 is the identification number for Acetaldehyde in the DOT Hazardous Materials Table (49 CFR §172.101).

What hazard class is UN1089?

UN1089 is listed under hazard class 3 (flammable liquid).

What packing group is UN1089?

Packing group for UN1089: I. Where several rows exist, the packing group that fits your material decides which row applies.

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Source: Hazardous Materials Table (49 CFR §172.101), eCFR.gov — current as of Oct 23, 2026. View the official table. Reference only — verify current requirements before shipping.