Aerosol Filtration Efficiency of Common Fabrics Used in Respiratory Cloth Masks

Face mask %FFE (SEM) for particles >300nm
N95 (no gap) 99.9 ± 0.1
N95 (with gap) 12 ± 3
surgical mask (no gap) 99.6 ± 0.1
surgical mask (with gap) 44 ± 3
flannel 44 ± 2
cotton (600 TPI), 1 layer 98.4 ± 0.2
chiffon, 1 layer 73 ± 2
natural silk, 1 layer 56 ± 2
hybrid 1: cotton/chiffon 99.2 ± 0.299.6 ± 0.1
hybrid 2: cotton/silk (no gap) 98.5 ± 0.2
hybrid 2: cotton/silk (gap) 32 ± 3
hybrid 3: cotton/flannel 96 ± 1