@Pat We don't promote those over N95s because in the community people are wearing #bettermasks and #n95s without fit testing, where we have data to show results in >90% fitted filtration efficiency in most.
AFAIK, not known if we get additional gains from N99 or elastomerics without fit testing - let me know if you have a reference on this.
For others reading this, the numbers @Pat is quoting are for the masks tested on a machine, glued to a plate around the edges. Fit testing N95s on people in occupational health and safety protocols require >99% protection as fitted filtration efficiency (ie, fit factor >=100). A large proportion of people will achieve this, particularly with novel designs of #BetterMasks like Vitacore's CaN99 and the 3M Aura. Average filtration not-fit-tested is usually reported >90% in lab studies. Studies summarized at https://maskevidence.org/mask-types
@Pat We don't promote those over N95s because in the community people are wearing #bettermasks and #n95s without fit testing, where we have data to show results in >90% fitted filtration efficiency in most.
AFAIK, not known if we get additional gains from N99 or elastomerics without fit testing - let me know if you have a reference on this.
For others reading this, the numbers @Pat is quoting are for the masks tested on a machine, glued to a plate around the edges. Fit testing N95s on people in occupational health and safety protocols require >99% protection as fitted filtration efficiency (ie, fit factor >=100). A large proportion of people will achieve this, particularly with novel designs of #BetterMasks like Vitacore's CaN99 and the 3M Aura. Average filtration not-fit-tested is usually reported >90% in lab studies. Studies summarized at https://maskevidence.org/mask-types