For many years, HEPA air filters have been used in air purifiers to filter particles. HEPA filters are well proven filtration devices and continue to be enhanced by many manufacturers. HEPA filtration guarantees the purifier will trap 99.97% of airborne particles larger than 0.3 microns. The human eye can’t see a particle smaller than 10 microns so many of the particulates captured cannot be seen, particularly bacteria and viruses. The filters found on room air conditioner models capture only large particles greater than 10 microns. For the smaller particles like dust, smoke, chemicals, pollens, and asbestos, HEPA filtration is needed.
The HEPA filtration component is essentially an accordion of very, very fine paper-like filter material. The material is loaded in an accordion or zig-zag fashion so that a very large surface area becomes available for air to be pushed through by the fan. Over time, the HEPA filter will become full and the airflow will no longer be able to move through the filter. HEPA filters typically last a number of years.
The more times the air in a room passes through a purifier with HEPA filtration, the cleaner the air will become. For the air purifier to be effective, it is important that it have the cleaning capacity for the size room in which it will be used. The specifications on the product will indicate what size room it is designed to clean. Read more about HEPA Technology.