35 healthy Shanghai college students used a purifier for 48 hours. Here’s what happened to their bodies

There are two things we know about purifiers and one really important thing we don’t know.   1. We know that purifiers reduce PM2.5   Loads of tests have found this in labs and in real-world homes. I’ve tested the hell out of this, in my room, in bigger rooms, for 200 days of Beijing air, comparison tests against the […]

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Plants Have No Detectable Air Purification Effect

Despite the popular conception that plants are purifiers, plants have detectable effect on particle or gas pollutants, according to the latest test data from real-world homes.   Belief that plants are effective air purifiers is widespread. Arguably the most frequently cited evidence is the NASA study on plants. It feels scientific, authoritative. This page cites it, this page, this page.   […]

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