It is the second time buying this itesm and I absolutely love it! Very silence and define toy do the work. Normally the air purifier is running all day long but if for some reason gets off I totally notice the different. I have one in the living room and just ordered this one for my bedroom. Is awesome how the air feel more clean and not heavy. Btw: I do work from home and the air purifier is very close to my desk and doesn’t bother me at all also, I have now in my bedroom and is running all night and the sound is so slow that don’t bother either me or my dogs while sleeping. Highly recommended