Assessment of Fabric Masks as Alternatives to Standard Surgical Masks in Terms of Particle Filtration Efficiency

Amy V Mueller; Loretta A Fernandez

To date, tests have been run on three commercially-produced, medical-type facemasks (masks with elastic ear loops and in-sewn wires to adjust fit to the bridge of the nose), and ten sewn, multi-ply cotton fabric facemasks of various designs (Table 1) . Masks were sourced from community volunteers currently producing masks for essential personnel working in human services; when possible multiple masks of each type were tested. Several of the fabric masks included filter layers such as cotton batting, Halyard H600 (sterilization wrap), and sections of HEPA vacuum bags. In addition, several sewn masks included hydrophobic interfacing layers (Pellon). Some masks included wires to fit the masks across the bridge of the nose (Table 1 : 3M, Staple, Charcoal, and Sewn Fabric Masks B and C); some did not (Table 1 : Sewn Fabric Masks A and D -J). Three N95 masks (3M model 1860) were also tested to confirm that >95% particle removal could be measured using the modified protocol.