Premi-air HM688S

The HEPA filter is 99.97% effective at removing particles down to 0.3 microns in one pass and 99% effective at removing particles down to 0.1 micron. The carbon filter helps to remove odours and the HEPA filter removes dust, animal dander, hair, mould spores and other airborne particles. Unless otherwise stated, the carbon filter should be replaced once every three to six months, the HEPA filter should be replaced once every 1 - 2 years. The air volume output will begin to decrease when the HEPA filter needs to be changed. Both the units below have HEPA filtration and are quiet on a low setting. If you need to effectively remove chemicals, the Roomaid, the HM685P or the Siestas are designed for that purpose.