The Really Small Stuff

To test how effective the DIY filter is, I’ve been posting lots of data on 2.5 micron particles. But my particle counter also measures smaller 0.5 micron particles, and I’ve been looking closely at that lately.     Remember that the “PM2.5” you hear in the news is different from the numbers on most particle counters. […]

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PM2.5 Particle Size Virus

The Newer, Cuter DIY Filter

My collaborator Gus Tate suggested we work with our HEPA manufacturer to get smaller, square HEPAs. Now we’re convinced the DIY filter just got a lot cuter: Cute and kicks PM 2.5 in the pants. Get the latest clean air tips!Get updates on masks, air purifiers and air quality delivered straight to your inbox.Thomas TalhelmThomas is an Associate Professor […]

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More Data!

A while back, I posted data comparing how effective the DIY purifier was compared to a 6,000 RMB Blue Air and 11,000 RMB IQ Air. In that test, I calculated effectiveness as percent difference from outside air. At the time, I said I didn’t like that way of calculating effectiveness, but I did it that way […]

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Filters and Fetuses

I don’t meant to be sensational, but I just got a picture from a friend of a friend who is pregnant and just started using the DIY filter three days ago. The filter is turning black already. After all, scientific research suggests children are the most affected by air pollution. If the outrageous prices of filters are keeping pregnant women […]

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