Cooking?  It clears the air.  Got a cold and don't want to infect the person who live it?  We put it by the bed and it has worked for years.  Dusting or vacuuming your home?  You'll see the sensor darken immediately as it senses the dust and pollutants and increases fan power.  Are you a smoker?  You'll immediately see the room clear.  The timer feature lets us use it with ease.

We've changed the filters regularly, and it works perfectly.