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Filtering efficiency of SMs against PM2.5.
| S. N. | Surgical masks (SMs) | Without filtration (μg/m3) mean ± S.D | With filtration (μg/m3) mean ± S.D | TIL (%) | Efficiency (%) |
|---|---|---|---|---|---|
| 1. | SM 1 | 20 ± 13.55 | 12.4 ± 10.32 | 62 | 38 |
| 2. | SM 2 | 28 ± 7.36 | 16.2 ± 4.32 | 58 | 42 |
| 3. | SM 3 | 26 ± 1.99 | 16 ± 2.52 | 62 | 38 |
| 4. | SM 4 | 25.8 ± 3.01 | 17.1 ± 6.06 | 66 | 34 |
| 5. | SM 5 | 21.6 ± 1.23 | 12.5 ± 2.76 | 58 | 42 |
| 6. | SM 6 | 20.6 ± 1.31 | 11.5 ± 3.72 | 56 | 44 |
| 7. | SM 7 | 24.3 ± 14.23 | 15.6 ± 12.9 | 63 | 37 |
