Sensly: an air quality monitoring HAT

Altitude Technology have a very interesting Kickstarter campaign that’s just entering its final few days. It’s for an Internet of Things air quality monitoring device called Sensly, and one of the interesting things about it is that it’s available either as a consumer unit or, considerably more cheaply, as a Raspberry Pi HAT.

Sensly's air quality monitoring HAT has applications at home and in education

Sensly will be able to detect benzene, carbon monoxide, formaldehyde, nitrogen dioxide, sulphur oxide, ammonia and polycyclic aromatic hydrocarbons; now that it has met its first stretch goal, it will also detect particulate matter such as pollen, smoke and mould spores, and backers will get this useful additional functionality for free. Temperature and humidity sensors are thrown in too. As with the Sensly consumer unit, the HAT version can communicate directly with your smartphone, giving you push notifications of high levels of pollutants, as well as uploading data for viewing (and, if you want, sharing) via a web browser.

We really like the idea of making a device available as a Raspberry Pi HAT as well as a boxed appliance so that you can hack and customise your own system, and the possibilities of this one are pretty broad. You could connect a camera board, for example, and investigate whether anything in particular happens to nitrogen dioxide levels when lots of Volkswagens are in the vicinity. Several unpleasant constituents of cigarette smoke are detected by Sensly, so you could quantify the effect of cigarettes on your air quality. With the addition of pH sensors, a number of the devices could monitor sulphur oxide levels and rainwater acidity across geographically distant locations over long periods; what patterns might be found in those data? And if I still lived aboard the fine narrowboat I used to own, I could save myself a considerable amount of anxiety by properly logging carbon monoxide levels and finding out how they actually varied with the use of our three cooking and heating stoves.

Narrowboat Roe moored on the Old West at sunset

Converted 1959 British Waterways River Class freight butty Roe moored on the Old West at sunset, and a heady quality of nostalgia. But there’s no point my hanging around here reminiscing; the past, as Elsa put it with memorable force, is in the past.

The team behind Sensly might be onto something when they argue, as they did in their winning pitch to Pitch@Palace On Tour recently, that making air quality more personal and tangible with a low-cost sensor system could motivate people to take action, and all sorts of recent news stories suggest that there is scope for paying a bit more attention to what we’re breathing. As a single example, evidence to the UK government’s consultation on air quality plans, released a week and a half ago, revealed that nitrogen dioxide exposure alone is causing an estimated 23,500 early deaths in this country each year.

Early-bird backers of Sensly’s Raspberry Pi HAT will get a device that shows them local levels of this and all kinds of other substances of interest for £25, but you’ll have to move quickly; the campaign closes this Saturday.