Amaircare air cleaners are individually tested to meet HEPA standards and beyond. This means that the complete air cleaner system will remove at least 99.97% of all particles as small as 0.3 microns (1/300th the size of a human hair or 0.000012 of an inch) that enter the air cleaner and are also 95% efficient at 0.1 microns. Features and Benefits Completely sealed and gasketed air cleaner system. Metal housing construction. Largest HEPA filter surface area for all air cleaners of comparable air