We use this unit upstairs of our home where the air can feel stale and dry. This unit does certainly humidify the air, and it appears to clean it as well. My daughter suffers from bad allergies, and if we get the slightest amount of rain, within just a few days she's having breathing issues because of all the pollen that gets kicked up. Since running this unit, we have had like 7 very rainy days, and while her allergies did flair up, they were much less then they have been in the past. A big plus for that!