AQUAVI Air 1000 HEPA & Activated Carbon Composite filterHEPA filters and activated carbon filters are two types of filters that can be used for air purification. HEPA filters capture particulates or solid air contaminants, while activated carbon filters absorb odor and chemical compounds. AQUAVI air purifiers combine both filters to achieve better results. HEPA filters can effectively filter out 99. 97% of 0. 3 micron particles, such as and very fine dust, so you will not be bothered by seasonal changes