Metal powders can be very dangerous!! Look up thermite, Using an aluminum abrasive disc and grinding or
cutting on steel (iron) will make a very fine thermite dust that if trapped in the carpet fibers and one day
the right stoichometric ratio and proper temp spark and you Will have a fire A very hot fire that can explode
if you put water onto it!! Keep a fire extinguisher handy, a dust mask, a scrap of linoleum or drop cloth and
clean up promptly. A bit of forethought and safety can save you even from things that seem trivial at the time
and not worth the bother. I like the sand/dust comment, Look up silicosis and you will have a new found
reason to only breathe through your nose when riding dusty trails or working.
It sure would suck to have your riding days shortened from a little dust or metal, Trust me it is NO fun not
having your lung capacity that you used to.