The Blue Pure 311 Auto air purifier takes a simple approach to air quality management with an integrated particle sensor， Auto mode setting， and LED air quality display. Independently evaluated for performance by the AHAM Verifide Program for a Clean Air Delivery Rate of 250 for fine smoke particles， 250 for pollen particles， and 244 for dust particles. Best for medium rooms like a master bedroom， living room， or playroom with a 360° air intake to filter room air about every 12 minutes (about 5x an hour at 388 sq.ft) on high. The 3-step filter works with HEPASilent filtration technology to remove 99.97% of airborne particles down to 0.1 microns， like pollen， dust， pet dander， mold， bacteria， viruses°， and more， while a layer of activated coconut carbon traps light household odors. Features a 3-color LED air quality display and one-touch enabled Auto mode setting to auto-adjust to real-time conditions. Noise levels equivalent to a whisper on low (30-52 dB)， and ENERGY STAR rated energy efficiency (7-35 W). Change color with five fabric pre-filters inspired by Scandinavian nature. Pre-filter in Arctic Trail (gray) included; Additional colors sold separately. All Blueair purifiers are AHAM Verifide for Clean Air Delivery Rate and recommended room size， ENERGY STAR rated， and tested by the California EPA Air Resources Board (CARB) for safe ozone emissions.This air purifier has not been tested against Coronavirus， and Blueair does not claim to capture， remove， or kill 2019-nCoV.