HazMat Tool — substance information

Carbon dioxide, solid or Dry ice

HMT May 2026

UN / ID: UN 1845
Hazard class: 9
Packing group: —
ERG guide: ERG 120
Special provisions: —
Source: 49 CFR §172 (2026/05)

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Carbon dioxide, solid or Dry ice

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 (2026/05)

(3) Hazard Class

9
Miscellaneous hazardous materials

(4) Identification number

UN 1845

(5) Packing Group

n/a

(6) Labels

None

(1) Symbols

This entry is signed with "A". The letter "A" denotes a material that is subject to the requirements of this subchapter only when offered or intended for transportation by aircraft, unless the material is a hazardous substance or a hazardous waste. A shipping description entry preceded by an "A" may be used to describe a material for other modes of transportation provided all applicable requirements for the entry are met.
This entry is signed with "W". The letter "W" denotes a material that is subject to the requirements of this subchapter only when offered or intended for transportation by vessel, unless the material is a hazardous substance or a hazardous waste. A shipping description entry preceded by a "W" may be used to describe a material for other modes of transportation provided all applicable requirements for the entry are met.

(7) Special Provisions (§172.102)

(8) Packing Authorizations (§173.***)

(8A) Exceptions	217	see 49 CFR §173.217
(8B) Non-bulk	217	see 49 CFR §173.217
(8C) Bulk	240	see 49 CFR §173.240

(9) Quantity Limits

(9A) Passenger aircraft/rail	200 kg
(9B) Cargo aircraft only	200 kg

(10) Vessel stowage

(10A) Location

Stowage category “C” means the material must be stowed “on deck only” on a cargo vessel or on a passenger vessel.

Source: 49 CFR §172.101(k)

(10B) Other

40	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.

No compatibility information for class 9 in 49 CFR §177.848 included.

Scope & sources (important)Click to show CFR references

This check evaluates segregation per 49 CFR §177.848. Additional loading/unloading and handling requirements may still apply; see 49 CFR §177 Subpart B (Loading and Unloading):

§177.834 - General requirements
§177.835 - Class 1 materials
§177.837 - Class 3 materials
§177.838 - Class 4 (flammable solid) materials, Class 5 (oxidizing) materials, and Division 4.2 (pyroforic liquid) materials
§177.839 - Class 8 (corrosive) materials
§177.840 - Class 2 (gases) materials
§177.841 - Division 6.1 and Division 2.3 materials
§177.842 - Class 7 (radioactive) material
§177.843 - Contamination of vehicles

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 1952	Ethylene oxide and carbon dioxide mixtures with not more than 9 percent ethylene oxide	2.2
UN 1010	Butadienes, stabilized or Butadienes and Hydrocarbon mixture, stabilized containing more than 40% butadienes	2.1
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
	n-Butyl peroxydicarbonate, with more than 52 percent in solution	Forbidden
UN 1058	Liquefied gases, non-flammable charged with nitrogen, carbon dioxide or air	2.2
UN 1379	Paper, unsaturated oil treated incompletely dried (including carbon paper)	4.2
UN 3466	Metal carbonyls, solid, n.o.s.	6.1
NA 9202	Carbon monoxide, refrigerated liquid (cryogenic liquid)	2.3