I bought two of this for my bedrooms a couple months back. My daughter has a medical condistion that requires clean air for breathing. . I was a little skeptical thinking the size of this puirfyer might not be adequate, Boy was I wrong! The air seemed so fresh and clean , and I feel that the airborne irrtants( dust,pollent pet dandra) just "disappeared. I loved . Sadly, I dropped one trying to transfer it to another room, so now I am on line order yet another to replace it and possiblly another for the spare bedroom. I high recommend this product!!