@masknerd · School districts, if you buy KN95's you have to vet the supplier. If you are dropping $300K on masks it only costs about $1K to get them tested at a legit lab. Otherwise they end up in my lab. Also 3 of 4 masks failed labeling requirements, 1st red flag

School districts, if you buy KN95's you have to vet the supplier. If you are dropping $300K on masks it only costs about $1K to get them tested at a legit lab. Otherwise they end up in my lab 😂.Also 3 of 4 masks failed labeling requirements, 1st red flaghttps://t.co/qXmYw5DUKU

— Aaron Collins (@masknerd) January 29, 2022

@masknerd Tested Masks Given out by MCPS to Teachers and Students Revealing Which are Fakes (not up to standards).

January 19, 2022 

@masknerd Aaron Collins tests masks given out to MCPS students and teachers.

Google Doc with MCPS mask test results from Aaron Collins.  Lines 453-457. 

CBS Mornings: Meet the Engineer who Tested the Masks Given out by @mcps @mocoboe

Not all masks are made equally, just ask @masknerd.

The aerosol scientist breaks down the best masks for filtration, fit and comfort — and how to spot which masks are legitimate. pic.twitter.com/8gqlLewJIP

— CBS Mornings (@CBSMornings) January 25, 2022

and more from Aaron Collins: 

The Guardian:  Aaron Collins on masks for the COVID-19 pandemic.