Radon is a highly dangerous pollutant. This sensor can detect it

If you're using an air purifier, how can you feel confident it's doing its job? And if you're not using one, how can you feel confident your air isn't poisoning you? Airthings of Oslo has a solution in the form of View Plus. It's a compact sensor about the size of a smart thermostat that can measure particles, carbon dioxide and VOCs – gases made by cooking, plastics and other sources. It can also measure the level of radon in the air of your home. That's a naturally occurring, radioactive gas that can have serious effects on your health, so it's good to know if it's present in your front room. 

A lot of modern air purifiers have sensors built in for pollutants and allergens – although not radon, on the whole. The Blueair DustMagnet for instance can detect particles as small as one micron, as well as cooking fumes and gases. However, where the sensors on air purifiers can be a bit of an afterthought, all the View Plus does is detect potentially unpleasant things in your air. It's not cheap either – the sensor costs £260/$299, whereas something like the DustMagnet is £349/$359 and that's designed to clean your air, not just warn you there's something wrong with it. So you'd hope it's doing a good job. 

View Plus has only just gone on sale but I've been trying it for the last 2 weeks. Thankfully all it's done so far is offer reassurance rather than warn me of impending, air-pollution-based doom.

View Plus proved easy to connect to my Wi-Fi, and its battery apparently lasts 'more than two years', so it's almost a case of fit and forget. Airthings says It can also be 'easily integrated into a smart home system using IFTTT, Google Assistant and Amazon Alex,' but I must admit I haven't felt the urge to do that. I don't really want Alexa warning me to flee the area in her lifeless voice.

Once you've placed View Plus – either on a suitable surface or attached to the wall – you need to wait for a week for its sensors to calibrate. I placed mine in the kitchen, which at my place is attached to the front room, giving plenty of potential for airborne unpleasantness. There's a Dyson Purifier Humdify + Cool in the front room portion of the space and a rotating assortment of devices from our best air purifier guide in the kitchen bit, as well as a standard extractor fan. 

The good news is, View Plus has largely given an only slightly more pessimistic view of this large dual-purpose room's air quality than the sensors on the two purifiers. 

Your view options on the View Plus itself are a very simple, current view of key air quality parameters or an even simpler one that says 'your air quality is good/fair/a nightmarish disaster.' However a much more in depth view can be gleaned from the Airthings View app.

The readings above are from first thing this morning and show that overall air quality is 'fair' rather than good due to the presence of VOCs. Perhaps that is inevitable, given that I used my Sage Pizzaiolo pizza oven last night, as that is a bit of a smoky beast compared to standard cooking. I also didn't leave any windows open due to the current storms buffeting the southern UK. 

What's interesting about this is that both the air purifiers in the space tell me that the air quality is excellent. So the main thing View Plus is doing for me is giving me worries where previously I didn't have any – something I've experienced before with air purity monitoring. It should be noted that my View Plus is not located close to either of my air purifiers – it's placed more centrally in the room, as I wanted to get a better overview of air quality.

Arguably more usefully, Airthings’ app will also give you a longer term view of all the various air quality aspects it tracks. So for this month so far I can see that everything is in the ‘good’ zone on average, apart from small particles, which strays into ‘fair‘ terrItory. I can only just tell this, since Airthings has gone with a system based on colour only, and for colour blind people like me, green and orange are not all that different. Why haven’t you also used text for this part of the app, Airthings? 

This is perhaps the one drawback with the View Plus. It can tell you about potentially quite serious issues with your home's air quality, but what are you then meant to do about it? The good news is that in many cases, it may simply be a matter of opening some windows. Or, if the pollution is coming from outside, closing some windows. However if Airthings' neat little smart sensor starts warning you of severe and ongoing issues with your air, you may find yourself having to splash out on air purifers or even structural changes to your home. 

Getting rid of radon in particular can be a costly business, involving sealing rooms and even the foundations of your house. Although that, admittedly, is preferable to lung cancer, for which radon is a leading cause.

Another slight anomaly with View Plus is that while it can detect PM1 (1-micron and below) particles, no data is shown on this in the app or on the device. You have to delve into what Airthings calls the 'web dashboard' to see PM1 data on its own. That may be an issue for some users, because some research suggests PM1 particles are worse for your health than the slightly larger – although still minute – PM2.5 ones. 

Airthings says, 'We chose to simplify particulate matter by showing only PM2.5 in our app to avoid confusion about the difference.' So while the PM2.5 reading includes PM1 as well, if you want PM1 on its own, head to the web dashboard. 

Quoting the World Health Organization, Airthings claims that '9 out of 10 people breathe unsafe air on a regular basis. The effects of allergens, pollution, wildfire smoke, radon and airborne viruses impact the health of people all over the world.'

With View Plus, you can be more informed about what pollution affects your home both at any given moment, and on a longer term, ongoing basis. What you actually do about it, however, is up to you. For me, it looks like I'm going to need to get just one more air purifier, to sit next to the View Plus in the middle of the room. And then there's the rest of the house to worry about.

Incidentally, View Plus also tracks temperature, humidity, air pressure and CO2 levels, so it's an all-round handy and informative device. 

Airthings View Plus: price and availability

Airthings View Plus is on sale now in the UK and USA, priced £260 and $299 respectively. It does not appear to be available in Australia at this point. 

• Buy from Amazon in the UK for £260
• Buy from Amazon in the USA for $299
• Find out more about the View Plus at Airthings.com.