For large rooms up to 508 square feet, this air purifier features advanced electronic control, VOCs sensor, 4 fan speeds including Turbo Setting to clear the air quickly, and Sleep Mode with programmable timer for quiet operation while saving energy. The True HEPA filter captures 99.97% of particles as small as 0.3 microns. A charcoal pre-filter traps odors and pre-cleans the air before it reaches the HEPA filter. Removes airborne allergens such as dust, pet dander, pollen, tobacco smoke, fabric fibers and mold spores. The Whispure™ Quiet System offers the quietest high efficiency air purifier technology*.