Whilst some of the presented facemask filtration efficiency percentages appear correct, some others are questionable …
+ typically facemask filtration efficiency must be certified by testing agencies.
+ it is acknowledged that Sponge Masks have low filtration, but how would it be possible that filtration is only between 0% and 0.5%?
+ and there are many types of Cloth Masks, some stretchable having rather low filtration,
+ whilst others are so thick that they would be close to 100% filtration (but are not breathable at all).
+ sharing vital public health information must not be done on broadbrush basis, ie must be done responsibly and where necessary, with qualifications
+ essentially, facemasks filtration efficiency must be tested and certified.
