dude i got rad ass air purifier it has this auto mode right where if the air is pure it doesn't do shit u can't hear it just sits there then if the air isn't pure it spins up and purifies the shit like i was sitting there and it starting making a lot of noise i was like bro wtf i just bought this fucking thing then i go past it towards the hall and it's mad smelly with cooking smells from down the hall that shit filtered it all i was like bro