Magnesium silicide

Magnesium silicide, Mg2Si, is an inorganic compound consisting of magnesium and silicon. As-grown Mg2Si usually forms black crystals; they are semiconductors with n-type conductivity and have potential applications in thermoelectric generators. 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 2624

(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.

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
A20	Plastic bags as inner receptacles of combination packagings are not authorized for transportation by aircraft. Browse special provision A20
IB7	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); Wooden (11C, 11D and 11F). Additional Requirement: Liners of wooden IBCs must be sift-proof. Browse special provision IB7
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
IP21	see 49 CFR §172.102
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
W40	see 49 CFR §172.102

(8) Packing Authorizations (§173.***)

(8A) Exceptions	151	see 49 CFR §173.151
(8B) Non-bulk	212	see 49 CFR §173.212
(8C) Bulk	241	see 49 CFR §173.241

(9) Quantity Limits

(9A) Passenger aircraft/rail	15 kg
(9B) Cargo aircraft only	50 kg

(10) Vessel stowage

(10A) Location

Stowage category “B” means

(i) The material may be stowed “on deck” or “under deck” on a cargo vessel and 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; and
(ii) “On deck only” on passenger vessels in which the number of passengers specified in paragraph (k)(2)(i) of this section is exceeded.

Source: 49 CFR §172.101(k)

(10B) Other

13	Keep as dry as reasonably practicable.
85	Under deck stowage must be in mechanically ventilated space.
103	Only to be loaded under dry weather conditions.
148	see 49 CFR §176.84

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