10-12-2009, 02:37 PM
A HEPA filter does more than just filter dust. It also filters odors, pollen, pet dander, and just about every other nasty thing that can be floating around. Including things such as dust mites. It is a big help to us people who have allergies and pets. I couldn't breathe without one, sometimes. (air filter, that is.) 
I only know what I know, and I don't understand very much of it, either.
Member: AEA, American Legion, Lions Club International
Motto: "Essayons"
Member: AEA, American Legion, Lions Club International
Motto: "Essayons"