True HEPA Filter captures 99.97% of dust and allergens as small as .3 microns such as household dust, pet dander, mold spores and plant pollens. Charcoal filter reduces common odors from pets, smoking and cooking.UV-C light technology works with Titanium Dioxide to kill airborne bacteria, viruses, germs and mold spores.22 inch 3 speed tower is best used for medium sized rooms and CADR rated 100+IMPORTANT: Use GENUINE Guardian Technologies replacement parts to maintain product performance and warranty. Only one single filter needs to be replaced every 6-8 months depending on the use of the product; Replacement filter is filter B - Model FLT4825 (ASIN B0055521W0) . To lengthen the life of your filter, a 4 pack of the carbon filters is also available - Model FLT22CB4 (ASIN B017ANUVC6). Voltage: 120V 60HzSafety certified by Intertek which is a Nationally Recognized Testing Laboratory. Certain units might produce mechanical noise during initial set-up which will subside after regular usage. Units are constantly life tested to insure the product meets the performance and durability expectations of the consumer.