Discover and read the best of Twitter Threads about #bestmasks
Most recents (1)
To the experts insisting “N95s are useless if not fit-tested”
Have you ever tried to fit test a “well-fit surgical mask” or “3 layered well-fit cloth mask”?
TLDR they are inferior.
A brief case series and 🧵
1/15
Have you ever tried to fit test a “well-fit surgical mask” or “3 layered well-fit cloth mask”?
TLDR they are inferior.
A brief case series and 🧵
1/15
There are two type of fit tests, 1) quantitative fit testing - a portacount machine measures the concentration of aerosol outside the mask versus inside the mask and 2) qualitative fit testing - a potent bitter or sweet aerosolized solution is inhaled under a hood
2/15
2/15
I underwent quantitative fit testing on a surgical mask, suboptimally fit KN95 and well fit CN99 (FFP3). The results were intuitive. The surgical mask, while still offering some protection, performed the worst.
3/15
3/15
