It’s a rare “blue sky” day in Beijing. The city is bathed in a beautiful late-afternoon light—the kind that makes people rush outside just to enjoy it. But rather than bask in the weather, a small group of expats and Chinese locals have instead chosen to hole themselves up in a café.

With screwdrivers in hand, the group hacks away at cheap blue plastic fans. A moment later, they strap onto the fans’ standard issue HEPA filters, gauze-like panels that are as white as bridal veils. In less than five minutes—and for less than $30—they’ve managed to construct an air purifier that the instructor of this DIY workshop claims is just as effective as professional models selling for thousands of dollars.

One of the workshop’s participants, a 27-year old PHD student named Gu Yaobao, is particularly pleased with his new machine. “I don’t understand why the professional purifiers have to be so expensive,” he says. “I’ve only seen them being sold in the last few years. Before, I had no idea about the effects of pollution on my body. Now I hear about it on the news, all these respiratory diseases it can cause, so I’ve bought plants, facemasks, everything.”

The Chinese government recently announced that it will invest $275 billion—an amount equivalent to Hong Kong’s GDP—over the next five years to combat air pollution. But many in China aren’t prepared to wait, and are taking matters into their own hands.

Nearly 3 million air filters were sold in 2012, an increase of roughly 50 percent on the previous year. And following January’s “airpocalypse”—a particularly nasty stretch of gray skies—demand skyrocketed even further, with the electronics giant Suning reporting that sales of filters rose 170 percent in the first four months of this year from the same period last year.

The rush to capitalize on China’s dirty air isn’t limited to large retailers. Small start-ups such as O2ganic promise to “clean air, naturally,” with plant packages that come in a variety of themes, such as “Mediterranean” and “Near and Dear.” Thousands more air-filtering plants are hawked by hundreds of small shops on Taobao (China’s version of eBay), with vendors highlighting exactly how many milligrams of indoor pollutants their green specimens can eliminate.

Face masks are also popular buys on the e-commerce website and come in a multitude of shapes and styles, from cuddly, fluffy panda faces and cartoon expression protectors to serious black numbers which cover the nose and mouth and make the wearer look like a comic book villain. Some retailers are pushing consumer choice a step further, selling customizable and company-branded anti-pollution masks.

One company, PureLiving China, goes even further: They offer to completely pollution-proof offices and homes. For $500 to $800, they will carry out a complete diagnostic assessment of inside air and water quality (“It’s better to know”, says their tagline) and suggest solutions, ranging from photocatalytic and oxidation treatments to the humble green plant. Founded in 2010 by a Chinese-American, the company initially catered almost exclusively to expats, but in the last six months they have had a flood of inquiries from Chinese families. “In January, traffic to our website was 30 times the usual,” says company spokesperson James Westwood. “Finally the pollution problem is becoming public knowledge. In the past, people would blame gray skies on fog.”

Interestingly, public awareness and the rising sales of anti-pollution products hasn’t actually coincided with consistently worse pollution. Using PM10, SO2 and CO as measures, pollution levels have actually dropped since 2006 in cities such as Beijing and Shanghai. PM2.5 measurements are less exact, as the government has not made these figures public in the last decade, but according to a study by U.S. scientists using satellite data average annual PM2.5 levels have slightly decreased or remained stable in cities including Beijing, Shanghai and Guangzhou.

Yet while the air may technically be getting cleaner, pollutants remain at worryingly high levels. Meanwhile, the increased willingness of the Chinese government to talk about pollution and to allow others to talk about it, coupled with a number of high-profile bad pollution days , has placed the air problem firmly on the public’s radar. Pollution levels, including PM2.5, are reported in Beijing weather reports and in January, this once-obscure term “PM2.5” received over 3 million mentions on Sina Weibo.

“I only really started to think about pollution as a problem after the government announced they would release data on PM2.5 at the beginning of the year,” admits Zhang Tianshu, an attendee at the DIY air filter workshop, whose first name, appropriately, means “comfortable sky.” “Before I just used to think Beijing wasn’t very sunny. Now I think I need several filters in my house.”

Public knowledge of China’s pollution may be growing, but understanding of what can be done to combat it is limited. Thomas Talhelm, a Fulbright scholar behind the Particle Counting website and an instructor at the DIY workshop, says that “people don’t know how to judge the value of an air filter or a face mask. They don’t have reliable information like we do in the U.S. with publications such as Consumer Reports. So it’s like wine: They use the price as their guide and assume the more expensive it is, the better.”

With a series of graphs, Talhelm shows that this trade-off isn’t necessary. At the end of the workshop, he brings out his particle counter, so that participants can test the $30 filters they’ve just made. As the screen clicks down to almost zero, excitement levels in the room rise. “It’s funny, now that the Internet knows I’ve been researching air purifiers, I keep getting blasted for ads for expensive machines. And I think, that’s where the money’s going, to pay for advertising,” says Talhelm. “It really bothers me when I see people ripping others off. I mean, rip them off when they’re on holiday, but this is their health we’re talking about.”