Spilled powder on the carpet...
Alan W. K.--For picking up POWDER I'd not have a concern with any vacuum cleaner--it's picking up primers where you don't want them going through the fan; the primers could be detonated.
No vacuum cleaner has the dirt going past the motor on its way to the collector bag--and the motor would be the only source of sparks. That'd be a dumb way to build a vacuum cleaner, as the dirt would gum up the motor in a short while.
If you have any concern about it, just make sure that the vacuum cleaner you use has the bag/filter/dirt catcher in front of the fan or air pump or what-have-you. I think all shop vacs are built this way.
Myself, for spilled powder (and I DO have carpeting in my reloading room) I use a hand-held vacuum that has the dirt bag before the motor. FWIW, mine is an Oryk XL. I'm not concerned if a live primer should escape my notice, and get sucked up into the Oryk. The primer would just settle in with the cat hair, shoe dirt, house dust, etc, etc, and no harm done.
I change dirt bags regularly; the filled ones go into the regular trash.