Dr. Saint Cyr recently pointed me to great tests of air purifiers from the Shanghai Consumer Protection Bureau: The reason this type of research is so badly needed is that Western research (like this report from Consumer Reports) focuses on allergens, not general industrial air pollution. Allergens are probably more relevant for most Americans, but […]
Science in the news! The word on clean air seems to be getting out. Particle Counting was written up in a few places recently: James Fallows graciously wrote about Particle Counting as one low-cost safeguard while living in “toxic” China, partly in response to New York Times Beijing correspondent Edward Wong’s personal account of worries […]
Independent Confirmation. I’ve always suspected that what I’ve “discovered” is so basic that people must’ve known about this before. Lo and behold, doctors at the University of Michigan recommend that people who suffer from allergies make a purifier for $25 with a furnace filter and a box fan. Getting independent confirmations of results is always important, […]
UPDATE: I now have directly comparable data with the DIYs, Blue Air, and Philips: Direct comparison tests. In earlier posts (1, 2), I showed that you can make an effective DIY air purifier to clean Chinese air pollution out of your home air. But just because the DIY filter is effective doesn’t mean it’s as […]
I think you can break the question of whether an air purifier works down into two questions. Is the air coming out of the purifier clean? This is the easier question to answer, and the test results are as clear as can be. The DIY purifier shoots out very clean air. But is that enough to actually […]
Does the DIY air purifier work? Test results (1, 2) give a conclusive answer, but this series of pictures gives a visceral answer. I took a picture of the HEPA about every seven days for four weeks. Glad that black gunk’s not stuck in my lungs instead. In static form, here’s Week 0 and Week […]
Here’s Test 1: Is the air that’s coming out of the filter clean? Is the HEPA trustworthy? See the filter in action. This settles that the air is coming out clean. But is that enough to actually clean the room air? See the room test data and how it compares to the Ferrari filters.
Based on my research into how different filters work, I concluded that a HEPA filter is all you really need to fight particulate air pollution in China. Given the fact fancy air purifiers run for 8,000 RMB here in Beijing, and I’m only here for a year, I thought I’d try making my own DIY […]
The beast. The Dylos DC1100 Pro Air Quality Monitor. This is what I use to test whether the filters work. It gives readings of the number of particles 2.5 micrometers and above, as well as .5 micrometers and above per .01 cubic foot. They’re available through Amazon for $261.