the 33 antibacterial disks of the "CleanCelⓇ" spin once every 45 seconds, partly submerged trough the fresh water tank and air is forced between the wet disks above the water line, cleaning the air of 95% of all air born particles per pass. Including nano particles 3 nanometers (nm) (the lower limit of current commercial particle counter capabilities) and larger. The ability, the air washing ability, of this product to filter particles less 200 nm (the HEPA lower limit) gives it the edge over standard HEPA air filter systems. I would give it 5 star's if it had a water tank auto fill capability. Other wise, it is very quiet, easy to use, easy to maintain, and is reasonably priced. I would love to see it produced as a 12 volt DC unit to use in my car too.