Typically it's about putting the straps on correctly and properly adjusting the nose bridge. When you don't put it on properly (i.e. straps above and below the

Typically it's about putting the straps on correctly and properly adjusting the nose bridge. When you don't put it on properly (i.e. straps above and below the ear, nose bridge properly adjusted) it'll be much less effective. See https://www.bu.edu/ehs/files/2014/08/N95-Respirators-Training.pdf https://www.bu.edu/ehs/files/2014/08/N95-Respirators-Trainin...