Atmosphere Replacement Hepa Filter The Atmosphere Air Purifier is backed by these strong certifications: AHAM  Certified by the Association of Home Appliance Manufacturers (AHAM) to the ANSI/AHAM AC-1-2006 CADR (Clean Air Delivery Rate) test protocol for the removal of airborne tobacco smoke,dust and pollen. ATMOSPHERE Air Purifiers certified CADR is 250 for tobacco smoke, dust, and pollen. U.S. EPAs ENERGY STAR  ATMOSPHERE Air Purifier exceeds the strict energy efficiency guidelines established by the United States Environmental Protection Agency for energy efficiency of room air cleaners. asthma & allergy friendly certified  The ATMOSPHERE Air Purifier was the first air purifier certified to be asthma & allergy friendly by the Asthma and Allergy Foundation of America and Allergy Standards LTD. Products carrying this certification mark have been scientifically tested and proven more suitable for people with asthma and related allergic sensitivities. Benefits Clarus Filtration 99.99% Effective. The Clarus filtration system features an activated carbon filter with a surface area large enough to cover 366 football fields. This abundant filtration capacity, along with an integrated HEPA filter and prefilter, effectively reduces odors, and effectively removes up to 99.99% of airborne pollutant particles that pass through the system. This includes contaminant particles such as pollen, bacteria, dust mites, viruses, smoke, and other impurities as small as .009 microns.