Magnesium

Stability: thermal, sunlight, metals

Description of key information

According to “ANNEX IX- STANDARD INFORMATION REQUIREMENTS FOR SUBSTANCES MANUFACTURED OR IMPORTED IN QUANTITIES OF 100 TONNES OR MORE, study for Stability and reactivity is only required if stability of the substance is considered to be critical.
Expert Judgement
The more massive a piece of magnesium, the more difficult it is to ignite, but once ignited, magnesium burns intensely and is difficult to extinguish. The storage recommendations in NFPA 480, Standard for the Storage, Handling, and Processing of Magnesium (hereinafter referred to as NFPA 480) take these properties into consideration. Recommended maximum quantities of various sizes and forms to be stored in specific locations are covered in this standard. Storage buildings should be noncombustible, and the magnesium should be segregated from combustible material as a fire prevention measure.
With easily ignited lightweight castings, segregation from combustible materials is especially important. In the case of dry fines (fine magnesium scrap), storage in noncombustible covered containers in separate fire resistive storage buildings or rooms with explosion venting facilities is preferable. For combustible buildings or buildings containing combustible contents, NFPA 480 recommends automatic sprinkler protection to assure prompt control of a fire before the magnesium becomes involved.
Because of the possibility of hydrogen generation and of spontaneous heating of fines wet with coolants (other than neutral mineral oil), it is preferable to store wet scrap fines outdoors. Covered noncombustible containers should be vented.
Magnesium in Magnesium Alloys is stable on storage and does not react with its container under normal conditions of use and storage. 
Therefore testing for Stability: thermal, sunlight, metals does not need to be performed. 

Additional information

According to “ANNEX IX- STANDARD INFORMATION REQUIREMENTS FOR SUBSTANCES MANUFACTURED OR IMPORTED IN QUANTITIES OF 100 TONNES OR MORE, study for Stability and reactivity is only required if stability of the substance is considered to be critical.

Expert Judgement

The more massive a piece of magnesium, the more difficult it is to ignite, but once ignited, magnesium burns intensely and is difficult to extinguish. The storage recommendations in NFPA 480, Standard for the Storage, Handling, and Processing of Magnesium (hereinafter referred to as NFPA 480) take these properties into consideration. Recommended maximum quantities of various sizes and forms to be stored in specific locations are covered in this standard. Storage buildings should be noncombustible, and the magnesium should be segregated from combustible material as a fire prevention measure. With easily ignited lightweight castings, segregation from combustible materials is especially important. In the case of dry fines (fine magnesium scrap), storage in noncombustible covered containers in separate fire resistive storage buildings or rooms with explosion venting facilities is preferable. For combustible buildings or buildings containing combustible contents, NFPA 480 recommends automatic sprinkler protection to assure prompt control of a fire before the magnesium becomes involved. Because of the possibility of hydrogen generation and of spontaneous heating of fines wet with coolants (other than neutral mineral oil), it is preferable to store wet scrap fines outdoors. Covered noncombustible containers should be vented.

Magnesium in Magnesium Alloys is stable on storage and does not react with its container under normal conditions of use and storage.

Therefore testing for Stability: thermal, sunlight, metals does not need to be performed.

Justification for classification or non-classification

Based on the hazard assessment of Magnesium in section 2.1 and 2.2 in IUCLID 5.4, available data for the substance and according to the criteria described in Directive 67/548/EEC and in the Regulation (EC) No 1272/2008 on classification, labelling and packaging of substances and mixtures (CLP Regulation):

 

 

Directive 67/548	Thermal stability R5 Heating may cause an explosion. R6 Explosive with or without contact with air.
CLP	Self-reactive substances and mixures H240: Heating may cause an explosion. H241: Heating may cause a fire or explosion. H242: Heating may cause a fire. Self-react. Type A Self-react. Type B Self-react. Type C Self-react. Type D Self-react. Type E Self-react. Type F Self-react. Type G

 

It is concluded that none of the above phrase has not to be assigned to Magnesium and   does not meet the criteria to be classified for Stability: thermal, sunlight, metals.