It’s 99% efficient at removing airborne particles such as dust, pollen, smoke, cat dander and mold spores. With extremely quiet operation, the purifier changes room air every 12 minutes. Permanent filters do away with expensive replacement costs. Electronic controls, three air cleaning levels and filter clean indicator. On/off oscillation disperses fresher, cleaner air. Washable for easy cleaning: Simply rinse the ifD™ filter four times a year. The energy-efficient device uses the same amount of power as a standard household light bulb.