It may well be that this particular Double-Masking is actually 85.4% …
But we really cannot tell, unless this particular Double-Masking Filtration Efficiency has been tested and is supported by a laboratory testing certificate
Then again, 85.4% is really not sufficient for protection
It is best that facemasks of at least 95% Filtration Efficiency are used
And there are facemasks offering at least 95% Filtration Efficiency, and SafeMask.Tech is one of them, offering 99.727%
