Mask Material Filtration Efficiency and Mask Fitting at the Crossroads: Implications during Pandemic Times

The COVID-19 pandemic triggered the widespread use and need for respirators face masks healthcare workers public. In this study, several generally available mask designs were fit tested, their materials evaluated filtration efficiency using 250 nm polystyrene latex particles. Efficiency testing was performed 2 0.5 h at low (2.6 L min–1) high (7.4 airflows, respectively, ~17.4 cm2 material area. As expected, all N95 KN95 passed test, showed efficiencies > 95% entire experiment both airflows. Of three air filters used in 3D-printed Montana masks, only HEPA filter had a Regardless of insert material, failed tests. Homemade duckbill made Halyard H600 sterilization wrap WypAll X80 reusable wipe also an average < To explain results, structure composition determined FE-SEM, IR Raman spectroscopy. conclusion, when highly efficient are that do not users properly, potential these to protect from aerosols is compromised. Therefore, design as important material.