You might not think there's gases like formaldehyde in your home, but it's released from paints and varnishes. This Dyson HEPA Cool Formaldehyde™ uses a HEPA filter to remove it from the air, alongside other nasties like benzene, bacteria or fumes. Air Multiplier technology draws air in to be purified, then circulates it right through the room. To keep your room fresh and clean, it senses and reports automatically on the LCD screen, so you'll always know what's going on.Good to know- The easy care filter is quick and simple to change, and there's automatic notifications on the fan- Diffused mode diverts air through the back of the machine so there's no breeze- For a peaceful night's sleep, this HEPA Cool Formaldehyde is 20% quieter than the previous model- The Dyson Link app lets you see what's going on and set schedules