The Honeywell tower air purifier is fitted with a True HEPA filter that clears the air of mold spores, dust, tobacco smoke, pollen, pet dander and other micro allergens. It captures up to 99.97% of air borne particles 0.3 micron or larger to improve the air quality in your room. It's also equipped with a carbon filter to take care of unpleasant odors. The electronic filter monitor lets you know when to change the filter. Works well for room sizes between 100 and 300 square feet. AHAM certified.