The Whynter EcoPure HEPA System Air Purifier Replacement HEPA and Activated Carbon Filter can capture 99.97% of viruses and bacteria from air that passes through the filters. This package includes a HEPA Filter that removes all air pollutants such as pollen, allergens, dust mites and an activated carbon filter that eliminates chemical fumes, toxic gases, smoke and other odors. It is recommended to replace the Whynter EcoPure HEPA system air purifier filter once every 4 – 6 months, depending on use and environmental conditions.