Table I.
Particle size integrated filter collection efficiency, air pressure drop, and quality factor for two surgical masks and one N95 FFR, which have undergone an autoclave sterilization under different conditions and decontamination treatment with a 70% ethanol
| Protective device | Condition | 30 L/min |
85 L/min |
||||
|---|---|---|---|---|---|---|---|
| Ec % | Δp mm wg | qf per mm wg |
Ec % | Δp mm wg | qf per mm wg |
||
| Surgical mask Lsp M-301 | New | 67.9 ± 2.2 | 0.8 | 1.42 | 53.9 ± 4.8 | 2.0 | 0.39 |
| Autoclaved × 1 | 60.8 ± 2.3 | 0.7 | 1.34 | 48.3 ± 6.4 | 1.7 | 0.39 | |
| Autoclaved × 5 | 57.2 ± 2.7 | 1.0 | 0.85 | 43.7 ± 6.2 | 1.8 | 0.32 | |
| Soiled+Autoclaved × 1 | 60.4 ± 3.1 | 0.7 | 1.32 | 29.6 ± 5.9 | 1.5 | 0.23 | |
| Soiled+Autoclaved × 5 | 49.4 ± 2.9 | 0.9 | 0.76 | 19.7 ± 6.2 | 1.5 | 0.12 | |
| Treated with 70% ethanol | 56.2 ± 4.2 | 1.6 | 0.52 | 51.1 ± 5.2 | 3.0 | 0.24 | |
| Surgical mask 3M 1818 | New | 92.3 ± 1.3 | 0.6 | 4.28 | 86.9 ± 2.3 | 1.5 | 1.36 |
| Autoclaved × 1 | 90.7 ± 0.8 | 0.6 | 3.96 | 84.8 ± 1.2 | 1.3 | 1.45 | |
| Autoclaved × 5 | 88.9 ± 0.7 | 0.7 | 3.38 | 81.9 ± 1.1 | 1.7 | 1.01 | |
| Soiled+Autoclaved × 1 | 89.1 ± 0.6 | 0.5 | 4.43 | 79.6 ± 1.2 | 1.6 | 0.99 | |
| Soiled+Autoclaved × 5 | 85.9 ± 0.8 | 0.6 | 3.27 | 79.0 ± 1.4 | 1.4 | 1.12 | |
| Treated with 70% ethanol | 74.5 ± 1.3 | 0.5 | 2.73 | 51.8 ± 2.4 | 2.0 | 0.36 | |
| N95 FFR 3M 1870 | New | 99.5 ± 0.8 | 3.1 | 1.74 | 96.9 ± 1.8 | 12.7 | 0.28 |
| Autoclaved × 1 | 98.2 ± 0.9 | 2.7 | 1.49 | 95.5 ± 1.1 | 9.6 | 0.32 | |
| Autoclaved × 5 | 97.1 ± 0.9 | 2.5 | 1.42 | 96.0 ± 2.1 | 8.4 | 0.38 | |
| Soiled+Autoclaved × 1 | 98.3 ± 1.1 | 2.4 | 1.69 | 96.0 ± 1.9 | 8.2 | 0.39 | |
| Soiled+Autoclaved × 5 | 97.6 ± 1.2 | 2.5 | 1.50 | 93.0 ± 1.8 | 8.8 | 0.32 | |
| Treated with 70% ethanol | 91.9 ± 1.1 | 2.7 | 0.93 | 80.2 ± 1.7 | 9.3 | 0.17 | |
Breathing flow rates = 30 L/min and 85 L/min.