The Honeywell hepa air cleaner model number 50300 really does what it says. It cleans the air. Most air purifiers, like ion producing air purifiers, actually make the air more polluted. Ionizers, according to Consumer reports, make more pollution in the air and can contribute to lung problems. They make dust heavier, and it falls down all over your furniture. This air cleaner, truely CLEANS the surrounding air. It is equipped with a charcoal filter that initially filters the air. The air then goes into a hepa filter where it is purified and cleaned even more. Then it is redistributed back into the room. My Honeywell air cleaner does a marvelous job of cleaning the air-it smells fresh and clean, and really does reduce the amount of dust in the room. When I remove the charcoal filter (it is replaceable) it is so dirty and dusty. That also helps preserve the hepa filter, which is much more pricey to replace. I have had this cleaner on every night for 2 years, and have not needed to replace the hepa filter. It has a handy gauge on top to show how dirty the filters are, so there is no guesswork as to when they need changed. I love my Honeywell air cleaner!