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Filtration Efficiencies of Various Mask Types

Flow Rate: 1.2 CFM
Filter Efficiency (%) Pressure Differential
Sample/Fabric <300 nm Average ± Error >300 nm Average ± Error ΔP (Pa)
N95 (no gap) 85 ± 15 99.9 ± 0.1 2.2
N95 (with gap) 34 ± 15 12 ± 3 2.2
Surgical mask (no gap) 76 ± 22 99.6 ± 0.1 2.5
Surgical mask (with gap) 50 ± 7 44 ± 3 2.5
Cotton quilt 96 ± 2 96.1 ± 0.3 2.7
Quilter’s cotton (80 TPI), 1 layer 9 ± 13 14 ± 1 2.2
Quilter’s cotton (80 TPI), 2 layers 38 ± 11 49 ± 3 2.5
Flannel 57 ± 8 44 ± 2 2.2
Cotton (600 TPI), 1 layer 79 ± 23 98.4 ± 0.2 2.5
Cotton (600 TPI), 2 layers 82 ± 19 99.5 ± 0.1 2.5
Chiffon, 1 layer 67 ± 16 73 ± 2 2.7
Chiffon, 2 layers 83 ± 9 90 ± 1 3.0
Natural silk, 1 layer 54 ± 8 56 ± 2 2.5
Natural silk, 2 layers 65 ± 10 65 ± 2 2.7
Natural silk, 4 layers 86 ± 5 88 ± 1 2.7
Hybrid 1: cotton/chiffon 97 ± 2 99.2 ± 0.2 3.0
Hybrid 2: cotton/silk (no gap) 94 ± 2 98.5 ± 0.2 3.0
Hybrid 2: cotton/silk (gap) 37 ± 7 32 ± 3 3.0
Hybrid 3: cotton/flannel 95 ± 2 96 ± 1 3.0

The filtration efficiencies are the weighted averages for each size range—less than 300 nm and more than 300 nm.

Table reproduced from Konda A, et al. Aerosol Filtration Efficiency of Common Fabrics Used in Respiratory Cloth Masks. ACS Nano. 2020;14(5):6339-6347.