Chromium trioxide, anhydrous

Chromium trioxide (also known as chromium(VI) oxide or chromic anhydride) is an inorganic compound with the formula CrO3. It is the acidic anhydride of chromic acid, and is sometimes marketed under the same name. This compound is a dark-purple solid under anhydrous conditions and bright orange when wet. The substance dissolves in water accompanied by hydrolysis. Millions of kilograms are produced annually, mainly for electroplating. Wikipedia

Substance Data

Source: TOXNET

CAS-Number

1333-82-0

Flash Point

n/a

Boiling Point

n/a

Emergency Response Guide No. 141

Data from the Hazardous Materials Table

Source: 49 CFR §172 (2018/07)

(3) Hazard Class

5.1
Oxidizers

(4) Identification number

UN 1463

(5) Packing Group

(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.

IB8	Authorized IBCs: Metal (11A, 11B, 11N, 21A, 21B, 21N, 31A, 31B and 31N); Rigid plastics (11H1, 11H2, 21H1, 21H2, 31H1 and 31H2 ); Composite (11HZ1, 11HZ2, 21HZ1, 21HZ2 and 31HZ1); Fiberboard (11G); Wooden (11C, 11D and 11F); Flexible (13H1, 13H2, 13H3, 13H4, 13H5, 13L1, 13L2, 13L3, 13L4, 13M1 or 13M2). Browse special provision IB8
IP2	When IBCs other than metal or rigid plastics IBCs are used, they must be offered for transportation in a closed freight container or a closed transport vehicle. Browse special provision IP2
IP4	Flexible, fiberboard or wooden IBCs must be sift-proof and water-resistant or be fitted with a sift-proof and water-resistant liner. Browse special provision IP4
T3	see 49 CFR §172.102
TP33	The portable tank instruction assigned for this substance applies for granular and powdered solids and for solids which are filled and discharged at temperatures above their melting point which are cooled and transported as a solid mass. Solid substances transported or offered for transport above their melting point are authorized for transportation in portable tanks conforming to the provisions of portable tank instruction T4 for solid substances of packing group III or T7 for solid substances of packing group II, unless a tank with more stringent requirements for minimum shell thickness, maximum allowable working pressure, pressure-relief devices or bottom outlets are assigned in which case the more stringent tank instruction and special provisions shall apply. Filling limits must be in accordance with portable tank special provision TP3. Solids meeting the definition of an elevated temperature material must be transported in accordance with the applicable requirements of this subchapter. Browse special provision TP33
W31	see 49 CFR §172.102

(8) Packing Authorizations (§173.***)

(8A) Exceptions	None
(8B) Non-bulk	212	see 49 CFR §173.212
(8C) Bulk	242	see 49 CFR §173.242

(9) Quantity Limits

(9A) Passenger aircraft/rail	5 kg
(9B) Cargo aircraft only	25 kg

(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

66	Stow “separated from” flammable solids.
90	Stow “separated from” radioactive materials.

Source: 49 CFR §176.84

Segregation Chart for Load, Transport, Storage

In this table a statement is contained for each hazard class whether the loading, transport or storage with other hazard classes is allowed, is not permitted or is restricted. The table is based on U.S.-Code 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

	May not be loaded, transported, or stored together in the same transport vehicle or storage facility.
	Load, transport, storage together is not restricted.
	Load, transport, storage together is allowed under restrictions.

Substances with similar name

UN-Number	Name	Hazard Class
UN 3165	Aircraft hydraulic power unit fuel tank (containing a mixture of anhydrous hydrazine and monomethyl hydrazine) (M86 fuel)	3
UN 1005	Ammonia, anhydrous	2.3
	Anhydrous ammonia, see Ammonia, anhydrous
	Chromic anhydride, see Chromium trioxide, anhydrous
UN 1768	Difluorophosphoric acid, anhydrous	8
UN 1032	Dimethylamine, anhydrous	2.1
NA 2927	Ethyl phosphonothioic dichloride, anhydrous	6.1
NA 2845	Ethyl phosphonous dichloride, anhydrous pyrophoric liquid	6.1
UN 1773	Ferric chloride, anhydrous	8
UN 1776	Fluorophosphoric acid anhydrous	8
UN 2029	Hydrazine, anhydrous	8
	Hydrobromic acid, anhydrous, see Hydrogen bromide, anhydrous
UN 1048	Hydrogen bromide, anhydrous	2.3
UN 1050	Hydrogen chloride, anhydrous	2.3
UN 1061	Methylamine, anhydrous	2.1
UN 1382	Potassium sulfide, anhydrous or Potassium sulfide with less than 30 percent water of crystallization	4.2
UN 3247	Sodium peroxoborate, anhydrous	5.1
UN 1385	Sodium sulfide, anhydrous or Sodium sulfide with less than 30 percent water of crystallization	4.2
UN 1083	Trimethylamine, anhydrous	2.1