Recent Filters Articles:

Types of Filters

Premise: This blog is for people concerned about air pollution. There are many valid reasons people want air purifiers: pet allergies, pollen, and asthma. However, these are not what I’m concerned about while living in China. Here I assess purifiers solely based on whether they can help protect me from particulate air pollution. With that […]

Read More »


Q&A

joshuaw81 提问: Hi Thomas, just started one of your cannon kits earlier today and it’s already turning gray. Already a fan of your work! Two quick questions for you: 1- I received a foam/fiber square that is white on one side and light green on the other. I’m assuming this is packaging, and not part […]

Read More »


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 […]

Read More »


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 […]

Read More »