Removes 99.97% of all airborne particulates, dust, pollen, molds, smoke, pet dander plus many gases and chemicals down to .3 microns and 95% of particulates 0.1 microns and smaller Every minute, 250 cubic feet of air is processed by a 4-5 stage filter that progressively removes contaminants from the air.These 4-5 stage air filters have a prefilter, a true medical grade HEPA filter and an activated carbon/zeolite filter which removes gases, chemicals and volatile organic compounds (VOC's) The standard unit has 15 lbs of carbon and 60 square feet of HEPA. The junior has 6.5 lbs of carbon and 30 square feet of HEPA. Emits no ozone ( which is classified as a respiratory irritant by the EPA) The all steel housing makes it safe for people with chemical sensitivities. Quiet with 3 speed operation. Air is drawn in at 360 degrees for strong air flow. The standard unit will clean an average bedroom in about 15 minutes with the door closed, up to 1,500 square feet. The Junior will clean up to 700 square feet. 6 air exchanges per hour in the room provide superior air quality. The motor is designed for continuous operation. Austin Air was chosen by the U.S. Government to fulfill the largest deployment of air cleaners in American history and chosen by FEMA and The Red Cross to address the serious air quality concerns in post 9/11 New York. 5 year warranty on motor, fan and other working parts. The filter carries a pro-rated 5 year warranty Replacement filters last 5 years with normal residential use for economical maintenance. Average operation cost is less than a penny per hour. American made in Buffalo NY. 5 year warranty. FREE SHIPPING on air filters in the continental US. Call 352-466-0193 or e-mail PERamseyer@gmail.com for more info.I have asthma, allergies and chemical sensitivities and use them in my home. They have changed my life.