The GermGuardian 3-in-1 Air Purifier is the best air purifiers for allergies. With the True HEPA filter, it captures 99.97% of dust and allergens as small as .3 microns such as pet dander, household dust, plant pollens and mold spores. The 22 inch 3 speed tower is good for medium sized rooms. This GermGuardian AC4825 Air Purifier features UV-C light technology that eliminates airborne bacteria, viruses, germs and mold using titanium dioxide. Charcoal filter reduces common odors from pets, cooking and smoke particles. Cool things to buy for your room, its sleek looking, very quiet, and Energy Star rated.