UN 3121Oxidizing solid, water-reactive, n.o.s.
Proper shipping name: Oxidizing solid, water reactive, n.o.s
Division 5.1
Oxidizing substances
Summary
UN 3121 is the UN number for oxidizing solid, water-reactive, n.o.s. It is classed in Division 5.1 (oxidizing substances) of Class 5 for transport. Packing group I or II, depending on the form. Emergency responders use ERG guide 144.
Emergency response
The Emergency Response Guidebook (ERG2024) guide for this number:
- Guide144Oxidizing solid, water-reactive, n.o.s.
From the 2024 Emergency Response Guidebook (ERG2024), published by U.S. Department of Transportation, PHMSA. Read the full guide in the ERG or on CAMEO Chemicals.
Identification
- UN number
- UN 3121
- Name
- Oxidizing solid, water-reactive, n.o.s.
- Hazard class
- Class 5: Oxidizers and organic peroxides
- Division
- 5.1: Oxidizing substances
- Packing group
- I, II
- What the class covers
- Substances which may cause or contribute to the combustion of other material, generally by yielding oxygen.
U.S. Hazardous Materials Table
2 entries share this number in 49 CFR 172.101, by name, packing group or where the shipment is going.
UN3121Oxidizing solid, water reactive, n.o.s
- Technical name required in parentheses
Special provisions: 62
- Class
- 5.1
- Packing group
- I
- Labels
- 5.1, 4.3
UN3121Oxidizing solid, water reactive, n.o.s
- Technical name required in parentheses
Special provisions: 62
- Class
- 5.1
- Packing group
- II
- Labels
- 5.1, 4.3
From the eCFR edition of 49 CFR 172.101 dated 2026-10-05 (section last amended 2026-09-08). The eCFR is an editorial compilation, not the official legal edition. Read the current table.
About Class 5
Class 5 covers substances that supply oxygen or otherwise intensify a fire. Division 5.1 is oxidizers such as ammonium nitrate and hydrogen peroxide; 5.2 is organic peroxides, which may also be thermally unstable.
Check the official sources
For emergency response, packaging and quantity limits, use these:
- CAMEO Chemicals: UN/NA 3121NOAA datasheets with the ERG response guide and isolation distances
- Emergency Response Guidebook (ERG)PHMSA's guide for first responders, free as a PDF or app
- 49 CFR 172.101 Hazardous Materials TableThe legal U.S. entry: proper shipping name, packing group, labels and special provisions