Thread by @FitTestMyPlanet

For engineers just tuning in to the #8020Agang scene now, a thread.
1/n

Back in 2022, @ghhughes started posting an interesting kind of mask test on his youtube channel . Broadly surveying common public health masks using condensing particle counting equipment originally used mostly for firefighting and military masks. 2/n

A test instrument with such a wide dynamic range might seem like overkill, but it ended up capturing a phenomenon entirely missed by bitrex tests, N95 mode, and PFE tests - a Pareto distribution of typical exposure reductions - even within masks with the same certifications.
3/n

N99/N100 mode is a more informative test than N95 mode test. It measures the overall reduction of exposure, implicitly requiring *both* good filtration and fit. In a Wild West era of unregulated Amazon products, it’s the only way to know for sure.
4/n

The tests didn’t worry about whose toes they step on. They were adversarial, so they didn’t focus on what the mask *could do*. There were relatively few mods, since most people use most products in the default settings, and this includes masks.
5/n