But air purifiers can also create a lot of noise, noted John McKeon, a former ER doctor and CEO and founder of international standards and certification outfit Allergy Standards. Sound from air purifiers originates in two key areas: the motor and the fan. A high quality air purifier should “blend” the sound of the fan and motor, eliminating noises like chopping through the air or an accompanying, annoying pitch, explained Poppy Szkiler, CEO and founder of Quiet Mark, a UK-based, independent accreditation firm that collaborates with the Noise Abatement Society on a shared mission to make the world (or at least your home) quieter. They aim to help consumers around the world find the quietest consumer tech products out there. And they don’t just test how loud a product is — they consider everything from the quality of emitted sound to noticeable vibration levels. If you’re looking for a new air purifier or hoping to upgrade to a quieter model, here’s where to get started shopping for demonstrably quiet air purifiers.
Quiet air purifiers: How Quiet Mark tests purifiers
Quiet Mark tests all elements of a product’s sound, including sound absorption, quality and volume. They accredit all types of home products, from electric toothbrushes to alarm clocks. While air purifiers may not strike you as the loudest appliance, their internal fans can produce a fair bit of noise, Szkiler told us. All air purifiers use fans to force air through a filter, which subsequently removes pollutants from that air. Running a purifier at a higher speed will typically create more noise, said McKeon. Where the purifier is located also matters — any sounds coming off of it may reflect off other surfaces and echo back, creating ever more noise. To that end, Quiet Mark owns a replica “kitchen” with tiled walls and floors to accurately test noise in a home setting.
Quiet Mark measures all products by the same criteria, but specifically tests air purifiers by listening to all available modes, including the ‘Sleep’ function, which most models equip. The most common sound metric is decibels — and while Quiet Mark takes decibel level into consideration while reviewing a product, they consider it just one aspect of the product’s “sound.” They also test sound quality, including tonalities and frequencies, and use jury testing to get direct consumer feedback.
Think of a mosquito, they aren’t loud but you soon notice when you have one in the room and the sound they make is very noticeable.
Typically, Quiet Mark-certified purifiers will have a low decibel range, though the organization doesn’t list decibels in its recommendations because the decibel range of a product can change depending on the environment the purifier is in, a spokesperson noted.
And while no air purifier is completely silent, the goal is to help shoppers find a model that releases a pleasant or non-intrusive sound, one that can easily fade into the background and won’t cause distraction. For example, while two purifiers could have the same decibel levels, one could emit a more irritating sound — which wouldn’t pass certification.
“There’s nothing more annoying than a constant disturbing noise when trying to drift off to enjoy a good night’s rest. Just because an appliance is quiet, it doesn’t mean it’s not disturbing. Think of a mosquito, they aren’t loud but you soon notice when you have one in the room and the sound they make is very noticeable,” said Szkiler. “Air purifier noise should easily fade into the background sounds and not be noticed.”
Quietest air purifiers
Without bothering to upgrade an air purifier, shoppers can easily improve the sound quality of an air purifier by keeping it in a room with carpet and other furnishings instead of a room with high ceilings and wood floors, Szkiler advised. Barring that approach, here are some of the quietest air purifiers out there, all of which Quiet Mark has certified. We verified decibel levels with respective manufacturers to maintain the relative comparison between models.
Blueair Pure 411 Air Purifier
- Sound level range: 17 to 46 decibels
The Blueair Pure 411 is ideal for smaller spaces, great to have in your home office or bedroom. The purifier is compact and comes in different colors to match your room’s decor. This model comes with the brand’s own HEPASilent technology (which is not the same as an approved, true HEPA filter) and a CADR rating — the entire bottom part of the model consists of a filter to trap as much particulate as possible. Besides being affordable, the Pure 411 has low-cost replacement filters and is more energy-efficient than other models.
Blueair Classic 480i Air Purifier
- Sound level range: 32 to 52 decibels
This larger air purifier from Blue is ideal for larger rooms or apartments, removing household chemicals, cleaners and odors from the air, in addition to larger particulate like dust and mold. Like the 411, it also comes with the brand’s HEPASilent technology in its filters and a CADR rating. This model can connect to Wi-Fi and integrate with other air quality sensors in your home.
Dyson TP02 Pure Cool Link Tower
- Sound level range: 46 decibels when set to Night mode
This purifier has a dual fan functionality, which rotates and circulates air throughout the room, covering up to 400 square feet. This model comes with a HEPA filter and can remove particulates as small as 0.3 microns. Other features include 10 airspeed settings and an automatic night mode to save energy. It can be linked to the Dyson app, which provides real-time air quality reports, and can be controlled remotely via smartphone or Alexa.
Dyson Pure Cool Link Purifier Fan
- Sound level range: 46 decibels when set to Night mode
This air purifier is more compact than the Cool Link Tower and can easily sit on your desk, cleaning the air all day long while you work. Similar to the Cool Link Tower, the Cool Link Purifier Fan doubles as a fan that oscillates throughout the date and has an energy-saving automatic night-time mode — it also has similar noise levels. Users can connect their fan to the Dyson app, which provides regular air quality reports.
Philips 3000i 2-in-1 Air Purifier and Humidifier
- Sound level range: 33 to 66 decibels
This smart purifier doubles as a humidifier and is ideal for dry rooms or apartments. It comes loaded with many features, including a sleep mode, three auto modes — general, allergen or sleep — and four pre-set humidity modes. Users can also choose to use both the humidifier and purifier at the same time, or just the purifier. The 3000i can remove particles as small as 0.3 microns via a HEPA filter.
How to find the right air purifier for you
Bedrooms typically host high levels of indoor air pollutants, including dust, bacteria and some viruses. Since we spend around a third of our days in bed, it’s all the more important we keep the air in our room clean. Opening a window is one way to get fresh air, but cold temperatures (and additional noise if you live in an urban area) may prohibit that option feasible.
Air purifiers, which are often labeled interchangeably with air filters and air cleaners, help remove indoor air pollution in a number of ways. Some trap and collect dirt and particulate in a filter, using a fan to draw pollution in. Other models use ultraviolet light sterilization or electrostatic filters to kill mold and bacteria, said McKeon. Importantly, there is currently no evidence that any air purifiers can completely filter the coronavirus Covid-19 out of the air.
If you’re looking for a less noisy air purifier, look out for the Quiet Mark “Q” logo to confirm it’s been independently certified, Szkiler said.
Most models will specify how many square feet they cover, and will list its CADR, short for Clean Air Delivery Rate. The CADR will show the volume of air that the purifier will clean in an hour. Typically, the larger your air purifier is, the higher the CADR will be, though you probably don’t need a large model for your bedroom, said McKeon — size matters.
“It’s no good getting a model which will struggle to clean the air in your room and, on the flip side, you don’t need one which is more suitable for a conference hall than your kitchen,” said Szkiler.
Quiet Mark said they test purifiers designed for all types of rooms, from as small a space as 15 square meters (approximately 161 square feet ) and up to 110 square meters (approximately 1,184 square feet). They haven’t found a direct correlation between purifier size and noise level. The same goes for efficiency – the company focuses on testing noise output, so shoppers should pay attention to metrics like CADR to determine efficiency. One efficiency designation is if the purifier has a HEPA filter, short for “high efficiency particulate air,” approved to do so by nonprofit Institute of Environmental Sciences and Technology. Quiet Mark only tests products with HEPA filters (or filters with similar efficiency levels), and the organization said these filters likely won’t increase the noise of an air purifier. Some filters need to be cleaned and replaced regularly, so take that into consideration while shopping.
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