Lasko’s Pure Platinum Air Purifier uses 3-stage filtration to remove smoke, odors, dust, allergens and more from the air. Stage 1 - Carbon filter: Removes smoke, cooking and household odors. Captures dust, pet hair and other large particles. Lasts up to 4 months. Extends filter life. Stage 2 - Pleated Filter: Removes 99% of airborne irritants (as small as 0.3 microns). Lasts up to 12 Months. Stage 3 - TiO2 filter with long-life UV light: Helps eliminate mold, bacteria and viruses. Removes odors and fumes from cleaners, aerosols, carpet and paint. Lasts up to 12 months.