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Support for your Dyson HEPA Big+Quiet Formaldehyde purifier

Dyson HEPA Big + Quiet Formaldehyde

Frequently asked questions

Why are there two airflow speeds?

Airflow speed 2 puts the purifier into maximum performance mode. Airflow speed 1 can be used for an even quieter experience to reduce disturbance in and around your business.

How noisy is the purifier?

Our latest purifier is acoustically engineered to operate quietly – even at its highest power setting. So it reduces your exposure to pollution, without disturbing you at the office or in the classroom. It records just 55dBA of sound power at full speed.

Where should I position the purifier in the room?

Your Dyson HEPA Big + Quiet Formaldehyde air purifier is engineered to purify a whole room.6 When placing the machine, make sure there's at least a few feet of clearance on all sides, so that the air can circulate effectively. Place away from air vents and windows. 

Should I keep the windows open or closed?

It depends on the CO₂ levels within your business at any one time. Our CO₂ monitor will alert you when levels are high – meaning it's time to increase ventilation by opening a window.7 If you're worried about outdoor air pollution, remember that your purifier will deal with them. 

Other purifiers claim “HEPA” standard – why is Dyson special?

In Dyson’s latest purifiers, it’s not just the filter that meets HEPA H13 standard, it’s the whole purifier.8 So they don’t just capture pollutants, they prevent them from leaking back into the air you breathe. High-pressure seals at 24 critical points, combined with Dyson’s fully-sealed filtration system, means our whole purifier meets HEPA H13 standard. So what goes inside, stays inside.

Were your previous purifiers ineffective if these new ones are fully sealed?

Our current purifiers still achieve HEPA H13 grade filtration. However, Dyson engineers are relentless when it comes to pushing the boundaries, which is why our latest purifiers feature further development, always providing the best possible purification to the end user.

Why do some competitor machines have a lower dB reading than Dyson purifiers?

Some manufacturers publish dB readings based on Sound Pressure levels, which can be easily manipulated by changes in the environment. They might also be tested at low fan speeds which can limit purification performance. 

At Dyson we measure and publish Sound Power levels dB(A) – the pure reading taken directly from the machine – at maximum fan speed, where purification is at its optimum.

What is formaldehyde?

Formaldehyde is a potentially harmful chemical found in many household products. A volatile gas, it can emit for years from woods, glues and fabrics found in household flooring and furniture. Particularly difficult to capture, it can quickly build up unseen and keep polluting for years.

Why is the Dyson catalytic filter better than carbon filter alone?

Many purifiers only have active carbon filters. But carbon is not designed to deal with formaldehyde – a pollutant which is particularly difficult to capture. This is because the pores can be too large for formaldehyde molecules and other gas molecules with higher adsorption forces tend to displace it. Our unique catalytic filter destroys formaldehyde permanently.9

Why does the new purifier have a CO₂ sensor?

Increased CO₂ levels can impact cognitive function. Our latest purifier senses and reports CO₂ levels and notifies when they exceed recommended levels, alerting on the LCD screen when to ventilate.7