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1144

UN 1144Crotonylene

Class 3

Flammable liquids

Summary

UN 1144 is the UN number for crotonylene. It is classed in Class 3 (flammable liquids) for transport. Packing group I. Emergency responders use ERG guide 128.

Emergency response

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

  • Guide128Crotonylene

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 1144
Name
Crotonylene
Packing group
I
What the class covers
Flammable liquids (and, in the U.S., combustible liquids).

U.S. Hazardous Materials Table

The entry for this number in 49 CFR 172.101.

  • UN1144Crotonylene

    Special provisions: T11, TP2

    Class
    3
    Packing group
    I
    Labels
    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 3

Class 3 covers flammable liquids such as gasoline, diesel, solvents, paints and alcohols. In the United States, some liquids with higher flash points can also be shipped as combustible liquids under the same class.

See all Class 3 UN numbers

Check the official sources

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