Catalytic technology reduces odors from smoke, pets, mold, mildew as well as harmful VOC's such as paint, varnish, nail polish removal, etc. Plug it in, turn it on and it goes to work! No expensive HEPA filter! Cartridge replacement is quick and easy and once a year! Effective in killing bacteria, superbugs (MRSA), and other airborne contaminants to protect your family and pets. No risks associated with the handling or discarding of contaminated or infectious filters.