From his hotel room on the 32nd floor, his view of the sprawling Chinese capital was totally obscured by smog. "It was all gone," Roosegaarde says. "The city was completely covered with smog." Two years later, he is taking the world's largest air purifier on a tour of China. The Smog Free Tower will create bubbles of clean air in inner-city parks and, Roosegaarde hopes, raise awareness of the dangers of air pollution. Rabbits love clean air, too The tower has just had a pilot run in Roosegaarde's hometown of Rotterdam, where his company, Studio Roosegaarde, is headquartered. It had a surprising effect on the local environment. "For some reason, little rabbits find the space around the tower particularly intriguing. I don't know why. Perhaps they can feel the difference," he says. Using ion technology, the tower attracts and captures the small pollution particles -- PM2.5 and PM10 -- and releases clean air, leaving the surrounding area with air that is about 75% cleaner, Roosegaarde says.

"Basically, it's like when you have a plastic balloon, and you polish it with your hand, it becomes static, electrically charged, and it attracts your hair." The seven-meter high tower can clean around 30,000 cubic meters of air each hour, which Roosegaarde says is "a small neighborhood a day." It runs on just 1,400 watts of power -- no more than a tea kettle. carburetor air cleaner spacerThe tower will arrive in China in September, starting with Beijing. where to spray air intake cleanerThe tour, a collaboration between Studio Roosegaarde and China's Ministry of Environmental Protection, will decide its subsequent city stops in China based on the results of a public online vote. military air purifierAfter China, Roosegaarde plans to bring the tower around the world -- Mexico City and India are destinations under consideration.

More than 80% of people in urban areas are exposed to air quality levels that exceed World Health Organization limits. As urban air quality declines, the risk of diseases such as strokes, heart disease, lung cancer, and asthma goes up. Small particles, PM10 and PM2.5, are particularly dangerous and affect more people than any other pollutant. The smaller the particle, the more dangerous it is -- PM2.5 being so tiny it can easily penetrate the blood and lungs. While all regions of the world are affected, populations in low-income cities are the most impacted, with 98% of cities there not meeting WHO air quality guidelines, compared to 56% of cities in high-income countries, according to recently released data from WHO. Roosegaarde says he has had requests from all over the world to make more towers, but cautions that it is not a miracle solution for improving air quality. "But I believe that creating a place where people can live, where they can feel the difference, smell the difference -- that is a very powerful motivator."

For him, it's more about drawing attention to the problem. "I hope that the designs I make will be part of a mentality change," says Roosegaarde. The tower doesn't just clean the air -- Roosegaarde's team also uses the smog it collects to make jewelry. The inspiration came from how diamonds are made in nature by compressed carbon. The tower collects compressed smog particles, which are partially made of carbon. They're put under high pressure for 30 minutes, sealed within a resin cube, and used in rings and cufflinks. "We have wedding couples buying it," Roosegaarde says. "They want to give each other true beauty." The first 1,000 rings and cufflinks have been shipped and people are asking for more. There is only one problem -- they have already run out of smog, Roosegaarde says. "But I am sure in Beijing we will catch up." The 36-year old designer founded his company Studio Roosegaarde in 2007 -- and calls it "the dream factory." Roosegaarde's other projects have included a Van Gogh inspired bicycle path run by solar-powered paint, and a dancefloor that generates electricity as people move.

He says he has always sought inspiration from his environment. "I am a guy who fell in love with places before I fell in love with girls. I always had a really strong connection with making places and experiences that you cannot download," says the designer. "And in a weird but beautiful way I became inspired by the Beijing smog."Isn’t it a total hassle to buy an air purifier in China, especially for expats? Back in places like the USA, when we shop for anything we can luxuriously research using consumer magazines and other review sources, wisely shopping around online and in stores as educated consumers. Here, many of us struggle with Chinese so are at a loss on local shopping websites, forcing us to rely on word of mouth and a tiny handful of imported brand stores. This usually has meant that many of us end up buying the same legacy brands, usually quite reputable but also usually at incredibly marked up prices. Even if fluent in Chinese it’s still very difficult to research credible data.

It’s a classic Economics 101 example of information asymmetry, where the typical consumer doesn’t have all the information that they need to properly research the marketplace, thus giving too much leverage to the seller — leading to a very unbalanced supply and demand curve where we pay much more than we should, for a machine that may not be exactly what we needed. So in my continuing efforts to educate people about healthy living in China and elsewhere, I’ve written a basic how-to guide to buying an air purifier, similar to my pollution mask buyer’s guide. I won’t be discussing the need to buy one, as I’ve made it blindingly obvious in many other articles that an air purifier is essential for anyone living here, especially children. Pre-step: Hire An Independent Testing Company I suggest that anyone with a villa, large home or a business should think about saving some time and possibly a lot of money first by hiring an environmental consultant to assess your site.

You may think famous Brand X air purifier is great — but do you need one, two, three or more? And can you get equal benefits from a much cheaper model? And which speed setting do you need to use for general use? Let them figure out all the complicated cubic meters and assess how much machine(s) you need. They also do a great job looking for — and fixing — air leaks around windows and doors (which is cheap and effective advice for everyone, even in your one-window tiny dorm room). They also are experts on the brands of machines available. They should also come back for free for a specified time and double-check that all is OK. I’ve personally used two such companies, both run by expats: Environment Assured, which aim to get your indoor PM2.5 concentration under 10 ug/m3 (the WHO standard, and my goal at home), and also PureLiving China, whose indoor goals for PM2.5 follow the higher Chinese target of 35 ug/m3. I’m sure there are other companies out there, as this surely should be a booming industry.

I personally think the evidence is overwhelming that your goal should be to keep your indoor PM2.5 under 10 ug/m3 all the time — even when the outside air is crazy bad. It can be done, and it doesn’t have to be as expensive as you fear. Step 1: How much/many do you need? Let’s do some math If your needs are simple or small, or you’re only here a few months, you can definitely handle this on your own. First, in order to know how much or how many machines you need, you first need to do some math: you need to calculate your room’s volume. Most air purifier ads mention either recommended room size (适用面积) as square meters or airflow rate (风机空载风量), often written as CADR, and listed as cubic meters per hour. Here are the steps: Let’s continue with my example as a case study, now that I know I need to get to 1050 m3/h for my front rooms. Comparing a couple of very large machines: Thus I could conclude that 2 Model A machines may be the most efficient choice for my needs, compared to 2 Model B machines, especially when it’s crazy bad outside and I want to crank up the machines to max speed for a few minutes.

On the usual settings I would need an equal amount of machines, but they’re both equally expensive so I’d just start with two of Model A, take some data for a while with my Dylos, and see whether I need to buy a third one. Step 2: How Much Budget? Not everyone can afford 12,000 RMB ($2,000 USD) for an air purifier, and the wonderful news is that nobody should be paying such exorbitant prices. Certainly when I arrived in Beijing eight years ago those very few early entry, imported brands served an invaluable service for expats and others. But now, there are many reputable brands making perfectly fine HEPA filters in China at a far more reasonable price point. For example, I’m pretty sure almost every student in China could sacrifice a few days of their Starbucks latte and buy the 200 RMB do-it-yourself air purifier. I also just published my own data proving that a slew of air purifiers under 1,000 RMB are perfectly fine for smaller rooms. I’ve tested most of the expat-famous imported models and yes, many are quite good, but I wouldn’t call most of them a good value for the money — not anymore.

of HEPA machines under 3,000 RMB which are rated for room sizes over 50 m2, including models from famous international brands such as Westinghouse, Philips, and Panasonic. In terms of features (工作原理), I strongly feel that you do not need ions (负离子) or ozone (臭氧) which actually can cause more lung harm than help — especially in the cheaper machines. Even UV lights (UV灯) are a bit gimmicky. I also don’t care much about killing bacteria (杀菌) and in my home formaldehyde (除甲醛) isn’t a big problem. Really, all you need is an awesome HEPA filter which clearly mentions it eliminates >99% of particles (过滤灰尘/花粉 (0.3 微米)), plus a strong fan speed which reflects in a high airflow/CADR. My second rank would be an activated charcoal filter (活性炭 滤网) which absorbs the sometimes serious indoor gases called VOCs, especially formaldehyde (甲醛) and benzene (甲苯). , which collects the most reputable reviews from multiple review sites such as Consumer Reports as well as reputable independent testers and also consumer reviews from Amazon.

But this is limited data for us in China as many of the brands aren’t the same here. I dearly hope there’s a Chinese version of such a useful site for Chinese consumers! In the meantime, I’m aware of a couple of independent reviews in China which I’ve blogged about here; I also found another Chinese-only review here. For other China-specific reviewers, I’ve blogged quite extensively about air purifiers and have reviewed many, which you can read here. My other favorite tests are from Thomas Talhelm, the creator of the 200 RMB Smart Air filter who also has extensive tests on his blog here. The next level of research are the online shopping stores. Each model is overwhelming you with pretty pictures and a hard sales pitch, but it’s here that you’ll find the details of CADR, filters, room sizes, and extras such as carbon, formaldehyde, etc. In China, online shopping has quickly become the most efficient way to buy almost anything, including air purifiers (空气净化器).

I recommend starting with Amazon China’s Clean Air Store, partly because on the left hand side you can instantly filter by square meters, price and features like HEPA. Also, for most English-speaking expats the Amazon store is much easier to use and very familiar to the USA version; they even have an English interface. ), especially if you click on their own distribution brands (京东配送); they also have excellent filter options. My last choices would be Taobao and Tmall. Of course there are retail stores as well but for research and convenience, not to mention price, online is great. What good is spending all this money on machines if your indoor PM2.5 still isn’t under the goal 10 ug/m3 all the time? I’ve saved a huge amount of money and also know that my indoor air is clean because I invested a bit in a portable particle monitor. Apparently you can buy online on Chinese sites but it’s cheaper (and probably safer) to get in the USA directly from them or Amazon. I hear that a lot of groups are pitching in to buy one and share, which is a terrific idea.

The goal with this Dylos is to get the data on the left side of the screen (PM0.5 but actually more represents PM2.5) always under 3,000, which correlates to an AQI of 50 (which itself means PM2.5 concentration under 12 ug/m3). It’s quite shocking just how many people buy machines and actually forget to change the filters, essentially making them totally ineffective if the filters get too clogged. It’s not only crucial to replace the filters on time (all machine replacement schedules are different), it’s also helpful to frequently wipe or vacuum the outside of the machine to get dust off the prefilters. I’ve had a Blueair for a long time — and totally forgot about the plastic prefilter screen underneath the machine, which was totally clogged with dirt and I’m sure was dramatically lowering the airflow. There simply is no longer any good excuse for anybody in China, even those with limited resources, not to protect themselves with an indoor air purifier. I hope I’ve provided some helpful information for you to make informed decisions.