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BlueAir dustmagnet 5240i review: A quiet and unobtrusive air purifier that really impresses

It’s energy efficient and doubles up as a side table

Qin Xie
Friday 22 April 2022 17:21 BST
It’s the brand’s most stylish model yet, with a grey and white colour scheme that will fit into any modern home
It’s the brand’s most stylish model yet, with a grey and white colour scheme that will fit into any modern home (The Independent )

Air purifiers have became one of the hottest gadgets to have in recent years as people spent more and more time at home amid the pandemic, and air quality became a focal point when there were so few other distractions. In fact, one report estimated that the global market for these devices grew by an impressive £220m between 2020 and 2021, and will likely double by 2030.

But with things returning to normal, and the air purifier market becoming increasingly crowded – we’ve tested a fair few ourselves – brands are having to do more to set themselves apart, whether it’s an improvement on price or new features.

In comes the new BlueAir dustmagnet, which was released in February 2022 and joins the budget-friendly BlueAir blue 3210 and the high spec BlueAir healthprotect 7470i in a line-up of Scandi-chic air purifiers. However, this one is designed to be even more visible, as it even doubles up as a side table. Another feature that sets it apart is that it’s designed to attract dust, which in theory means less cleaning. Always game for saving time, we had to try it for ourselves.

How we tested

There are two sizes of the BlueAir dustmagnet – the 5440i and the 5240i. There’s a price difference of £50 between them and a slight capacity difference, but we went with the smaller model because it was perfectly adequate for our home and wouldn’t take up as much room – an important consideration when you live in an inner city flat.

Over several weeks, we put the device through its paces, looking at how it behaves in different rooms, how easy it is to use and how sensitive it is to things like cooking odours. We also did a big clean beforehand so we could check whether it did indeed reduce how frequently we had to do housework.

Read more:

BlueAir dustmagnet 5240i air purifier: £349,

  • Fan setting: Three speed setting plus auto and night
  • Quiet Mark certification: No, but we expect it will given its noise level is 23 - 47 dB(A)
  • Oscillation: No
  • Remote control: Via app, or smart home devices including Amazon Alexa, Google Home or Tmall Genie
  • Timer: Via app
  • Power: 4 - 22W
  • Warranty: One year, or five if you register
  • Weight: 4.5kg
  • Height: 52cm
  • Max width: 22cm


We think the dustmagnet is BlueAir’s most stylish air purifier yet. It has a grey and white colour scheme that will fit into most modern homes and, while it’s designed to be visible, it doesn’t feel intrusive.

The device is raised 9cm off the ground by four grey plastic legs that simply screw on. The main body is a cuboid with rounded edges, featuring a grey fabric panel on the front and back, an air outlet panel on either side and an air inlet on both the top and the bottom. Unlike other BlueAir devices, this one has two separate filters – one at the top and one at the bottom – that are accessible from the back, where the in-built sensor is located. Both of these also have a wire pre-filter that needs to be cleaned regularly.

In the “roof” area, there are four white plastic stilts that raise the slightly concave top tray 5cm above the top air inlet. This grey plastic top tray transforms the device into a side table, and is ideal for relatively light items like a book or your glasses – although you definitely shouldn’t rest any drinks on top of it.

There’s also a discrete control panel on the right, front corner of the device, next to the top air inlet. Here, you can turn the device on, choose the fan speed and check the filter status. Most of the functions are selected via the app, though. There’s no display panel, only tiny LED lights to show you the setting.


The dustmagnet 5240i is designed for rooms of up to 20m2, which is more than enough for most homes – for reference, the bigger 5440i will handle rooms of up to 33m2 but the average UK living room is only 17m2. For its recommended room size, the 5240i can completely clean the air inside every 12.5 minutes, taking out everything from pollen and dust to bacteria and viruses.


The device is equipped with the brand’s signature HEPASilent technology, which combines the power of a HEPA (high efficiency particulate air) filter with that of an electrostatically charged environment to increase the rate at which it can clean the air, reduce energy consumption and make the whole process quieter. It works because the particles in the air become charged and are drawn to the filters, rather than being forced through multiple filtering layers as in the case of true HEPA filters.

The wire pre-filters are also charged on this device to help attract dust to the air inlets. The idea is that they are drawn to the air purifier before they get a chance to settle on the floor or on your furniture, which hopefully in turn means less cleaning for you – more on that below.

Some of the other features are pretty standard for high tech air purifiers. There are three fan speeds to play with as well as an auto and night mode. On auto mode, the device automatically adjusts the fan speed according to the readings on the in-built sensor, while on night mode it’s basically on the lowest level with the lights off. You can toggle between the different settings on the app, or set a schedule and let the device get on with it.

Read more: BlueAir’s healthproject is 7470i is a small but mighty specialist air purifier


Having already tested a couple of BlueAir devices, the set up for the dustmagnet felt pretty straightforward. There is a little bit more assembly – the legs need to be screwed on and you need to unwrap two filters instead of just one – but everything else is intuitive.

The only bit of confusion we experienced was which way up the filters should be inserted. Theoretically, the two filters should be facing in opposite directions as the air is entering the device from different directions but it turns out they are both meant to be facing up. There is actually a direction indicator printed on the filter, but it’s unhelpfully hidden underneath the piece of ribbon that you use to pull the filter out from the device.


For us, it felt like the dustmagnet was midway between the healthprotect and blue 3210 in terms of sensor sensitivity. It didn’t react as strongly when we cooked, for example, but did go into overdrive when we used hair spray. But even though the fan speed didn’t seem to pick up much, we did feel that the air was noticeably cleaner when it was on with the windows closed versus when it was off and we had the windows open.

In terms of being a namesake dust magnet, we’re not entirely convinced. Our home was certainly less dusty compared to normal after continuous use but the reduction wasn’t enough to warrant us cleaning any less. Plus, as temperatures warm up, we foresee having the window open more regularly, which would mean leaving the DustMagnet off during the day – this, we think, would inevitably mean more dust in our home.

It’s worth noting that a substantial amount of dust does get trapped in the pre-filter and when you switch off the device, they’ll fall into a pile underneath. And when you come to clean the pre-filter, it can get pretty messy. In both cases, you’ll need a trusted vacuum cleaner handy and maybe even a face mask if you’re particularly sensitive to dust.

Read more: BlueAir blue 3210, a whisper-quiet air purifier on a budget

The verdict: BlueAir dustmagnet 5240i air purifier

We liked the dustmagnet 5240i a lot. It’s quiet, unobtrusive and a great size for smaller homes. It also makes a great side table – it’s just a shame that you can’t put a drink on top of it.

For the price, we think it represents pretty decent value for money although it might cost a little more for upkeep. This is mainly because the filters are meant to be replaced every six to 12 months, at £55 each time. The device is very energy efficient though, so won’t add too much to your electricity bill, even if you have it on all the time.

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