I've had this thing running non-stop for about 2 months in my bedroom. I've knocked it over, the cats knock it over, my boyfriend tripped and knocked it over. We smoke, have pets that can be stinky, a teenager who can by really stinky, carpet that's dander and dust collecting. This thing rocks! It puts up with a lot of abuse. I keep checking the filter, but it's good. I'm going to buy more because they only cover 700 square feet - that's a room about 35x20 feet for those of you who are curious.