Air Purifier by Guardian Technologies. Improve your indoor air quality. This HEPAFresh air cleaning tower uses a multi-layer filter system to capture allergens and reduce household odours. The all-in-one filter is simple to replace when needed. HEPAFresh filter captures 99% of airborne particles, such as dust mites, debris, mold spores, pollen and pet dander. The charcoal filter layer captures household odours. The pre-filter extends the life of the HEPAFresh filter by capturing large particles, lint, and pet hair.