HazMat Tool — substance information

Crotonic acid, liquid

HMT May 2026
UN / ID
UN 3472
Hazard class
8
Packing group
III
ERG guide
ERG 153
Special provisions
SP IB8, SP T1
Source
49 CFR §172 (2026/05)

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Crotonic acid, liquid


Crotonic acid ((2E)-but-2-enoic acid) is a short-chain unsaturated carboxylic acid described by the formula CH3CH=CHCO2H. The name crotonic acid was given because it was erroneously thought to be a saponification product of croton oil. It crystallizes as colorless needles from hot water. With a cis-alkene, Isocrotonic acid is an isomer of crotonic acid. Wikipedia

Emergency Response Guide No. 153

Hazardous Materials Table

Source: 49 CFR §172 (2026/05)

(3) Hazard Class

8
Corrosive liquids

(4) Identification number Help

UN 3472

(5) Packing Group Help

III

(6) Labels Help

Corrosive liquids (8)

(7) Special Provisions (§172.102) Help

×Note:
Special provisions may be very complex. The extracts are taken from 49 CFR §172.102. Please be careful with the information, as necessary, additional conditions may be applied that are not written here. Please check the original source and report bugs.
IB8
T1

(8) Packing Authorizations (§173.***) Help

(8A) Exceptions154see 49 CFR §173.154
(8B) Non-bulk203see 49 CFR §173.203
(8C) Bulk241see 49 CFR §173.241

(9) Quantity Limits Help

(9A) Passenger aircraft/rail5 L
(9B) Cargo aircraft only60 L

(10) Vessel stowage Help

(10A) Location
(10B) Other

Segregation chart for load, transport, and storage

This chart shows whether loading, transport, or storage with other hazard classes is permitted, prohibited, or restricted. Based on 49 CFR §177.848.

Prohibited Must not be loaded, transported, or stored together in the same vehicle or facility.
Permitted May be loaded, transported, or stored together.
Restricted May be loaded, transported, or stored together only with restrictions.

Similar substances

UN / IDProper shipping nameHazard class
UN 2823Crotonic acid, solid8