Viruses, bacteria, mold, chemicals and particles go through 4 levels of filtration for complete removal of airborne microorganisms such influenza and gastro. Airpura's 18 lbs. of custom  blended activated carbon adsorbs chemicals, VOC's, gases, and odors while a medical grade True HEPA filter provides powerful  particle reduction of 99.97% of particulate matter as small as 0.3  microns including PM2.5, pollen, dust, dander. This UV air purifier also has a UV light that provides an additional level of protection against pathogens. Effective for rooms  up to 2,500 square feet. Provides a complete air exchange every 30 minutes.