While living in Beijing, China, University of Virginia graduate student Thomas Talhelm created a cheap alternative to the expensive air purifiers being used in China to combat the air pollution. via Science Blog:

He also became one of the millions to suffer from the sometimes-lethal air pollution, the result of massive coal burning during a cold snap and China’s growing love affair with motor vehicles. Beijing alone has more than 1 million cars on the road.

“I had to use a mask when I biked,” Talhelm said during a recent phone call from Beijing, where he has returned to do follow-up work on his rice theory paper. “I felt like I had asthma and it hurt to breathe deeply.”

Those who could afford it were resorting to an expensive solution: air filters costing up to $1,000. Because he was only going to be in Beijing for eight months, Talhelm was unwilling to lay out that kind of cash. “I thought it was pretty ridiculous. And on top of the sticker price, they really stick you for the replacement filters,” Talhelm said. “I could have afforded it, but if you are gouging me, it’s unfair. And there are plenty of people who cannot afford it.”

His solution was remarkably simple and really cheap. He strapped a HEPA filter to a fan and quickly began to enjoy clean air. A particle counter he purchased confirmed the filter was effective.