UNunnums
1942

UN 1942Ammonium nitrate, with not more than 0.2 percent of combustible substances, including any organic substance calculated as carbon, to the exclusion of any other added substance

Division 5.1

Oxidizing substances

Summary

UN 1942 is the UN number for ammonium nitrate, with not more than 0.2 percent of combustible substances, including any organic substance calculated as carbon, to the exclusion of any other added substance. It is classed in Division 5.1 (oxidizing substances) of Class 5 for transport. Packing group III. Emergency responders use ERG guide 140.

Emergency response

The Emergency Response Guidebook (ERG2024) guide for this number:

  • Guide140Ammonium nitrate, with not more than 0.2% combustible substances

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 1942
Name
Ammonium nitrate, with not more than 0.2 percent of combustible substances, including any organic substance calculated as carbon, to the exclusion of any other added substance
Hazard class
Class 5: Oxidizers and organic peroxides
Division
5.1: Oxidizing substances
Packing group
III
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

The entry for this number in 49 CFR 172.101.

  • UN1942Ammonium nitrate

    with not more than 0.2% combustible substances, including any organic substance calculated as carbon, to the exclusion of any other added substance

    Special provisions: 148, A1, A29, B120, IB8, IP3, T1, TP33

    Class
    5.1
    Packing group
    III
    Labels
    5.1

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.

See all Class 5 UN numbers

Check the official sources

For emergency response, packaging and quantity limits, use these: