Tower Air Purifier with permanent filter offers quiet oscillating operation and 99 percent efficient at capturing a variety of harmful indoor air particles such as: smoke, dust, pollen and pet dander. QuietClean air purifier circulates and filters the room air every 12 minutes. Air purifier includes a washable filter and LED touch button controls with three air cleaning levels. Air purifier is designed for a 13' x 13' (170 square feet) room. An electronic indicator reminds you when to simply rinse the filter in water four times a year. Air purifier is certified by the Association of Home Appliance Manufacturers. Energy Star qualified.