http://www.woodshopnews.com/news/fea...s-of-wood-dust

Nice article.

How OSHA currently judges with a paper clip.

"So is the sawdust in my facility a hazard? It depends, Scott says.
The really dangerous stuff is so-called “wood flour” — fine particles
500 microns or smaller."

It appears to be a very small chance.

However as far as I am concerned the breathing of the "wood flour" is
my concern, so I will be paying attention, to this for my sake.

Steel wool catches fire easily, just so as you are aware of it. I like
to bet that I can set steel on fire. Haven't lost yet.