I am a smoker and have used many different kinds of air purifiers, trying to rid the awful smell of cigarette smell in my home. Not until I tried this Honeywell Tower Air Purifier w/ Ionizer, did I realized what a clean room smelled like, even with smokers. In less than 2 hours, this air purifier improved the air quality 500%, that my spouse, a non-smoker, commented that she could now spend more time in the same room as me, while I smoked. I don't feel so terrible now, smoking up a storm or having other smokers all lite up at once as this unit can handle cleaning the smoke and letting others breath, pure fresh indoor air, again, without opening windows.