The Plasmacluster 7,000 Series KC850U Air Purifier with Humidifier by SHARP is ideal for medium-sized rooms. Effective up to 1,230 sq. ft. at one air change per hour, the KC850U will filter the air in the AHAM Suggested Room Size of 254 sq ft. at 4.8 air changes per hour. The SHARP long-life True HEPA filter and the long-life Activated Carbon filter last up-to 5 years, depending on the environment. The KC850U meets the strict energy efficiency criteria to earn the ENERGY STAR Rating. The KC850U is AHAM Verifide Tested to provide a Clean Air Delivery Rate (CADR) for three common irritants and allergens, Smoke (164), Dust (164), and Pollen (174). It is certified by the California Air Resources Board (CARB) to meet its strict emission standards. The KC850U features Max, Med, and Low fan speeds, plus Pollen, Quick Clean, and Auto Mode. The KC85OU includes a humidifier that may make your home more comfortable.