We bought a new foam mattress which started off- gassing. It was being impossible to live in the home during to smell. So to help with cleaning out the indoor air, we bought this purifier. I could breathe the difference soon after. Have been using it daily in different rooms and I surely feel the air is more cleaner and odorless. I would surely recommend it. 4 star because I find the room colder when the purifier is on. However, my husband doesn't agree to the room being colder. But otherwise a good product overall and definitely recommend it.