FIG. 9.
Filtration efficiency (FE) of an N95 respirator (black), the N95 base fabric (red), a surgical mask (blue), and a twill (magenta) as a function of particle mobility diameter (Dm). The basic sample is represented by solid bold lines, whereas the reneutralized samples are represented by dashing lines. The indigo starts to represent the twill FE as determined by an aerosol particle mass analyzer and reneutralization. In FE, the uncertainty is 5%. Reproduced with permission from Zangmeister et al., “Filtration efficiencies of nanoscale aerosol by cloth mask materials used to slow the spread of SARS-CoV-2,” ACS Nano 14(7), 9188–9200 (2020).39 Copyright 2020 American Chemical Society.