Is Magnesium ok?

[Alan Anderson]

The caution against getting it wet might be confusing magnesium for sodium (or potassium or another alkali metal). While it does burn spectacularly as a powder or shavings (or when molten), there is a significant difference between alkali metals and alkaline earth metals. Sodium reacts with water and is likely to ignite the hydrogen produced by the chemical reaction. Magnesium only has issues with water when it's already burning.

[DonRotolo]

As many have noted, Magnesium in typical form is no more dangerous than any other metal - even underwater. However, smaller chips or particles are able to be ignited, and then become extremely difficult to extinguish.

Yes a class D extinguisher has a chance, but hav limited effectiveness and are costly.

If you use the metal and don't need to machine it, you'll be fine. But if it needs to be machined, you are better off avoiding it. The risk is small but the consequences very large.

[BBray_T1296]

Originally Posted by Mike Schreiber

Wasn't the housing on the NI cRIO magnesium? No one started any fires - although hopefully no one was machining it.

No, it was almost certainly certainly steel. Those things were heavy!