Which metal is noted for posing an explosive dust hazard?

Which metal is noted for posing an explosive dust hazard?

• A. Iron
• B. Magnesium
• C. Aluminum
• D. Copper

Answer: (B)

Finely divided metal dust can form an explosive mixture in air, and magnesium is especially prone to this hazard. When magnesium is in powder form, it ignites and burns very readily, and if the dust is dispersed in a confined space, the combustion can propagate rapidly and cause an explosion. This makes magnesium the metal most associated with explosive dust hazards in welding and metalworking environments. Iron and copper dust are less likely to form explosive clouds, and aluminum dust, while also a concern, is not as notoriously explosive as magnesium in typical shop conditions.

Finely divided metal dust can form an explosive mixture in air, and magnesium is especially prone to this hazard. When magnesium is in powder form, it ignites and burns very readily, and if the dust is dispersed in a confined space, the combustion can propagate rapidly and cause an explosion. This makes magnesium the metal most associated with explosive dust hazards in welding and metalworking environments. Iron and copper dust are less likely to form explosive clouds, and aluminum dust, while also a concern, is not as notoriously explosive as magnesium in typical shop conditions.