HazMat Tool — substance information

Carbon dioxide, refrigerated liquid

HMT 15 June 2026

UN / ID: UN 2187
Hazard class: 2.2
Packing group: —
ERG guide: ERG 120
Special provisions: SP T75, SP TP5
Source: 49 CFR §172 (15 June 2026)

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Carbon dioxide, refrigerated liquid

Carbon dioxide is a chemical compound with the chemical formula CO2. It is made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in a gas state at room temperature and at normally-encountered concentrations it is odorless. As the source of carbon in the carbon cycle, atmospheric CO2 is the primary carbon source for life on Earth Wikipedia

Substance Data

Source: PubChem (HSDB, 09.12.2019)

CAS-Number

124-38-9

Flash Point

n/a

Boiling Point

n/a

Emergency Response Guide No. 120

Hazardous Materials Table

Source: 49 CFR §172 (15 June 2026)

(3) Hazard Class

2.2
Non-toxic, non-flammable gases

(4) Identification number

UN 2187

(5) Packing Group

n/a

(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.

T75	When portable tank instruction T75 is referenced in Column (7) of the § 172.101 Table, the applicable refrigerated liquefied gases are authorized to be transported in portable tanks in accordance with the requirements of § 178.277 of this subchapter. Browse special provision T75
TP5	For a portable tank used for the transport of flammable refrigerated liquefied gases or refrigerated liquefied oxygen, the maximum rate at which the portable tank may be filled must not exceed the liquid flow capacity of the primary pressure relief system rated at a pressure not exceeding 120 percent of the portable tank's design pressure. For portable tanks used for the transport of refrigerated liquefied helium and refrigerated liquefied atmospheric gas (except oxygen), the maximum rate at which the tank is filled must not exceed the liquid flow capacity of the pressure relief device rated at 130 percent of the portable tank's design pressure. Except for a portable tank containing refrigerated liquefied helium, a portable tank shall have an outage of at least two percent below the inlet of the pressure relief device or pressure control valve, under conditions of incipient opening, with the portable tank in a level attitude. No outage is required for helium. Browse special provision TP5

(8) Packing Authorizations (§173.***)

(8A) Exceptions	306	see 49 CFR §173.306
(8B) Non-bulk	304	see 49 CFR §173.304
(8C) Bulk	314, 315	see 49 CFR §173.314, 315

(9) Quantity Limits

(9A) Passenger aircraft/rail	50 kg
(9B) Cargo aircraft only	500 kg

(10) Vessel stowage

(10A) Location	D Stowage category “D” means the material must be stowed “on deck only” on a cargo vessel or on a passenger vessel carrying a number of passengers limited to not more than the larger of 25 passengers or one passenger per each 3 m of overall vessel length, but the material is prohibited on a passenger vessel in which the limiting number of passengers is exceeded. Source: 49 CFR §172.101(k)
(10B) Other	n/a

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.

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 0222	Ammonium nitrate, with more than 0.2 percent combustible substances, including any organic substance calculated as carbon, to the exclusion of any other added substance	1.1D
UN 1942	Ammonium nitrate, with not more than 0.2% combustible substances, including any organic substance calculated as carbon, to the exclusion of any other added substance	5.1
UN 1041	Ethylene oxide and carbon dioxide mixtures with more than 9 percent but not more than 87 percent ethylene oxide	2.1
UN 3150	Devices, small, hydrocarbon gas powered or Hydrocarbon gas refills for small devices with release device	2.1
UN 1010	Butadienes, stabilized or Butadienes and Hydrocarbon mixture, stabilized containing more than 40% butadienes	2.1
UN 1952	Ethylene oxide and carbon dioxide mixtures with not more than 9 percent ethylene oxide	2.2
UN 3300	Ethylene oxide and carbon dioxide mixture with more than 87 percent ethylene oxide	2.3
	Di-n-butyl peroxydicarbonate, with more than 52 percent in solution	Forbidden
	Dibenzyl peroxydicarbonate, with more than 87 percent with water	Forbidden
	Diethyl peroxydicarbonate, with more than 27 percent in solution	Forbidden
UN 1058	Liquefied gases, non-flammable charged with nitrogen, carbon dioxide or air	2.2
	n-Butyl peroxydicarbonate, with more than 52 percent in solution	Forbidden
UN 1379	Paper, unsaturated oil treated incompletely dried (including carbon paper)	4.2
UN 3281	Metal carbonyls, liquid, n.o.s.	6.1
UN 1361	Carbon, animal or vegetable origin	4.2