Magnesium hydride

Magnesium hydride is the chemical compound with the molecular formula MgH2. It contains 7.66% by weight of hydrogen and has been studied as a potential hydrogen storage medium. For comparison, one cubic meter can contain 45 kg of hydrogen pressurized at 700 atm, 70 kg of liquid hydrogen, or up to 106 kg of hydrogen bound in magnesium hydride. Magnesium hydride is also investigated for use in thermobaric weapons and incendiary weapons, standalone or as a mixture with a solid oxidizer; China tested a (non-nuclear) "hydrogen bomb" using the substance. It can be also used in emulsion explosives as a source of bubbles and additional fuel. It can be added to improve heat release of aluminized explosive compositions and to improve burn rate of propellants. Wikipedia

Emergency Response Guide No. 138

Data from the Hazardous Materials Table

Source: 49 CFR §172 (2018/07)

(3) Hazard Class

4.3
Dangerous when wet materials

(4) Identification number

UN 2010

(5) Packing Group

(6) Labels

Cargo Aircraft Only (Cargo Aircraft Only)

(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.

A19	Combination packagings consisting of outer fiber drums or plywood drums, with inner plastic packagings, are not authorized for transportation by aircraft. Browse special provision A19
N40	This material is not authorized in the following packagings: a. A combination packaging consisting of a 4G fiberboard box with inner receptacles of glass or earthenware; b. A single packaging of a 4C2 sift-proof, natural wood box; or c. A composite packaging 6PG2 (glass, porcelain or stoneware receptacles within a fiberboard box). Browse special provision N40
W32	see 49 CFR §172.102

(8) Packing Authorizations (§173.***)

(8A) Exceptions	None
(8B) Non-bulk	211	see 49 CFR §173.211
(8C) Bulk	242	see 49 CFR §173.242

(9) Quantity Limits

(9A) Passenger aircraft/rail	Forbidden
(9B) Cargo aircraft only	15 kg

(10) Vessel stowage

(10A) Location

Stowage category “E” means the material may be stowed “on deck” or “under deck” 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 is prohibited from carriage on a passenger vessel in which the limiting number of passengers is exceeded.

Source: 49 CFR §172.101(k)

(10B) Other

13	Keep as dry as reasonably practicable.
52	Stow “separated from” acids.¹ ²
148	see 49 CFR §176.84

¹For waste cyanides or waste cyanide mixtures or solutions, refer to §173.12(e) of this subchapter.

² Class 8 materials in PG II or III that otherwise are required to be segregated from one another may be transported in the same cargo transport unit, whether in the same packaging or not, provided the substances do not react dangerously with each other to cause combustion and/or evolution of considerable heat, or of flammable, toxic or asphyxiant gases, or the formation of corrosive or unstable substances; and the package does not contain more than 30 L (7.8 gallons) for liquids or 30 kg (66 lbs.) for solids.

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 1418	Magnesium, powder or Magnesium alloys, powder	4.3
UN 1419	Magnesium aluminum phosphide	4.3
UN 1622	Magnesium arsenate	6.1
	Magnesium bisulfite solution, see Bisulfites, aqueous solutions, n.o.s.
UN 1473	Magnesium bromate	5.1
	Magnesium dross, wet or hot	Forbidden
UN 2853	Magnesium fluorosilicate	6.1
UN 2950	Magnesium granules, coated, particle size not less than 149 microns	4.3
UN 1869	Magnesium or Magnesium alloys with more than 50 percent magnesium in pellets, turnings or ribbons	4.1
UN 1475	Magnesium perchlorate	5.1
UN 2011	Magnesium phosphide	4.3
	Magnesium scrap, see Magnesium, etc. (UN 1869)
UN 1928	Methyl magnesium bromide, in ethyl ether	4.3