AeraSmart™ Sensor monitors the air quality and automatically adjusts the fan speed to keep your air purified. True HEPA filter with AeraSafe™ antimicrobial treatment safely removes 99.97% of airborne particles as small as 0.3 microns, including pollen, ragweed and other allergens, viruses, germs, dust mites, mold spores and cigarette smoke. Ultra quiet operation. Filter Change Indicators let you know when it is time to replace your Carbon or True HEPA filter AM III. Commercial air purifier cleans the air of common areas such as waiting rooms, restrooms, and other large spaces with high concentrations of contaminants. Patented EnviroSmart™ technology detects the environment and automatically adjusts performance. Cleans the air of 300-700 square feet spaces. 5 Year Limited Warranty.