This highly effective air purifier captures 99.97% of the microscopic particles (0.3 microns & larger) that pass through its filter.Honeywell True HEPA air purifiers are efficient at capturing airborne pollutants like dust, pollen, pet dander, mold spores, & tobacco, cooking & fireplace smoke particles.This model also captures certain bacteria & virus from the air passing through the filters. With a slim design & easy-to-use controls, this air purifier uses a mechanical filtration process, meaning that a fan pulls the particle-filled air into the unit & forces that air through a HEPA filter, effectively cleaning & circulating the air in the room up to five times an hour. And, Honeywell True HEPA Air Purifiers do not release ozone back into the air from the filtration process, making them the preferred option of Allergists. Air Cleaner Machine Type: True HEPA; CADR: 124 (Dust); 117 (Pollen); 110 (Smoke); Maximum Room Size (Square Footage): 170 sq ft; Maximum Room Size: 12 x 14.