The Honeywell True HEPA Allergen Remover Air Purifier removes at least 99.97% of common household particles as small as 0.3 microns from the air passing through the filter such as dust, pollen, mold spores, tobacco smoke, and pet dander. The carbon activated pre-filter helps remove common household odors while keeping your house smelling lovely and fresh. The patented 360 degree air intake and discharge maximizes efficiency circulating the air and allowing for placement in any area of your room. This air purifier also features the Intelli-Check filter monitor to remind you when to replace the pre-filter and clean the HEPA filter. Simply vacuum to clean filter. Statistics are from the air that passes through the filter. Overall particle reduction is dependent on many factors, including the amount of air processed, the pollutant type, and the pollutants introduction rate into the environment.