HazMat Tool — substance information

Maleic anhydride, molten

HMT May 2026

UN / ID: UN 2215
Hazard class: 8
Packing group: III
ERG guide: ERG 156
Special provisions: SP T4, SP TP3
Source: 49 CFR §172 (2026/05)

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Maleic anhydride, molten

Maleic anhydride is an organic compound with the formula C2H2(CO)2O. It is the acid anhydride of maleic acid. It is a colorless or white solid with an acrid odor. It is produced industrially on a large scale for applications in coatings and polymers. Wikipedia

Substance Data

Source: PubChem (HSDB, 13.12.2019)

CAS-Number

108-31-6

Flash Point

n/a

Boiling Point

n/a

Emergency Response Guide No. 156

Hazardous Materials Table

Source: 49 CFR §172 (2026/05)

(3) Hazard Class

8
Corrosive liquids

(4) Identification number

UN 2215

(5) Packing Group

III

(6) Labels

(7) Special Provisions (§172.102)

×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.

Minimum test pressure (bar)	2.65
Minimum shell thickness	§ 178.274(d)(2)
Pressure-relief requirements	Normal
Bottom opening requirements	§ 178.275(d)(3)

Browse special provision T4

TP3

The maximum degree of filling (in %) for solids transported above their melting points and for elevated temperature liquids shall be determined by the following:
TP3

Where: d_f and d_r are the mean densities of the liquid at the mean temperature of the liquid during filling and the maximum mean bulk temperature during transport respectively.

Browse special provision TP3

(8) Packing Authorizations (§173.***)

(8A) Exceptions	None
(8B) Non-bulk	213	see 49 CFR §173.213
(8C) Bulk	240	see 49 CFR §173.240

(9) Quantity Limits

(9A) Passenger aircraft/rail	Forbidden
(9B) Cargo aircraft only	Forbidden

(10) Vessel stowage

(10A) Location

Stowage category “A” means the material may be stowed “on deck” or “under deck” on a cargo vessel or on a passenger vessel.

Source: 49 CFR §172.101(k)

(10B) Other

53	see 49 CFR §176.84
58	see 49 CFR §176.84
95	see 49 CFR §176.84
102	see 49 CFR §176.84

Source: 49 CFR §176.84

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.

Note: In this segregation and separation chart are HazMat of hazard class 8 considered depending if there are liquid. Currently HazMat Tool is not able to to check if a HazMat is liquid or not. Therefore it is assumed as liquid. See PHMSA Interpretation #09-0252.

Hazard class	8	7	6.1	5.2	5.1	4.3	4.2	4.1	3	2.3B	2.3A	2.2	2.1	1.6	1.5	1.4	1.3	1.1/1.2
1.1/1.2
1.3
1.4
1.5
1.6
2.1
2.2
2.3A
2.3B
3
4.1
4.2
4.3
5.1
5.2
6.1
7
8

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

Similar substances

UN / ID	Proper shipping name	Hazard class
UN 2698	Tetrahydrophthalic anhydrides with more than 0.05 percent of maleic anhydride	8
UN 2214	Phthalic anhydride with more than .05 percent maleic anhydride	8
UN 2215	Maleic anhydride	8
UN 1715	Acetic anhydride	8
UN 2739	Butyric anhydride	8
UN 2496	Propionic anhydride	8