Johan Wennerström is the brains behind Blueair’s groundbreaking air purifier technology. And it all started off with a chance meeting

“Look! This has only been in Addis Ababa for one week!” Johan Wennerström from Blueair points at a pitch-black filter on his computer screen. The filter has been inside an indoor air purifier in the Ethopian capital. It shows both how bad air pollution can be in some parts of the world and how committed Wennerström is to improving the air that we breathe. Almost all of Blueair’s air purifiers have been invented by him.

But let’s start from the beginning, because Wennerström was with Blueair right from the beginning. As is often the case, this story started off with a random meeting. During the early 1990s, Wennerström was working as a researcher and teacher at the KTH Royal Institute of Technology in Stockholm, where he had graduated as a civil engineer after specializing in heating and ventilation technology. One day, a certain Bengt Rittri came to visit. At that time, Rittri was working for Electrolux, the Swedish home appliance maker, which wanted to collaborate with the university on an air purifier it was developing. With his background in anything and everything to do with filters, Wennerström was the perfect man for the job. However, it all came to nothing and the years went by. After completing his licentiate degree, Wennerström joined the Stockholm office of a German company with active carbon filters for ventilation systems and protective suits for decontamination after CBRN (chemical, biological, radiological and nuclear) warfare. But then the company decided to close down its operations in Sweden. “On the very day that I was informed about the closure and I was on my way home, I met Bengt in the doorway. He had decided to start up his own company in air purification and he was going around meeting lots of different people who could be potential partners. And, well, I was only unemployed for half a day!” Wennerström says.

That was when Blueair was founded, a two-man operation with Wennerström as production developer and Rittri as managing director. So started an inten - sive period of researching and testing for Wennerström who wanted to develop a filter system and purifier for the consumer market. “It took about six months but then I discovered what is now known as HEPASilent™ technology and it is still being used today,” Wennerström says.

The combination of mechanical filtration and an encapsulated ion particle charging chamber meant that the air from Blueair purifiers has as much as 99.97 percent of its airborne particles removed, or even more when it comes to larger particles such as pollen. It is thanks to this technology that Blueair has grown to become the company it is today. Yet Wennerström is nothing if not humble and unassuming. While he admits that he’s “not bad at filtration”, at the same time he sees his role in Blueair’s expansion and success as mostly down to chance. “I just sort of stumbled over this really. My degree project was about particle filters and my licentiate thesis was about gas filters, and then I just happened to meet Bengt.” His main interest is everything that is linked to buildings, especially indoor climate: from heating systems to windows, incoming sunlight, wind, ventilation and purification. Everything is connected to the air. “My fundamental idea has always been that an air purifier must do precisely that, purify air. Not add anything to it. Quite simply, our indoor air must become cleaner. Some companies make machines that add aroma, that spray things into the air to improve it, but to me that is not an air purifier. For me, it’s all about dirty air in and clean air out. That’s it!”

When Wennerström starts to explain his reasoning, it becomes obvious how consumer-focused his product development philosophy is. He is adamant that all of Blueair’s air purifiers must meet four criteria: they must have a low noise level; low energy consumption; be designed so that people will want to have an air purifier in their living rooms; and then, the thing that other engineers would perhaps have bragged about first, they must have as high a clean air delivery rate (CADR) as possible.

“Another fundamental idea that is getting stronger and stronger over time is that every new air purifier we develop must have its own story,” Wennerström says. Blueair Sense is a good example. It has a glass top and instead of press - ing buttons, you just move your hand over it. “It has attracted a lot of attention and also won prizes for its design. No one else has an air purifier like it.” Clean breathing air is Wenner - ström’s driving force. He remembers the contrast between the first time he was in Beijing in 1990, when everyone cycled and almost nobody drove a car, and the terrible year of 2013. That was when air pollution rocketed and people could see how bad it was. The American embassy started to take its own readings and pronounced it “crazy bad”. “The way the situation was then, the only thing you could do was buy an air purifier. That was when things really took off for us,” Wennerström says.

Everything we do produces pollutants and when there are a lot of people in a small area more pollutants are created. But even in “clean” environments, an air purifier is beneficial. A good particle filter does not distinguish between different particles and can therefore reduce the spread of infectious agents in, for example, healthcare settings. “So an air purifier is not only good for your health; it’s also good for hygiene,” says Wennerström who loves fresh air of any kind. “For my part, the air in Stockholm’s archipelago is unbeatable.”