Table 2.
The effect of an elastic band worn over the beard on the fitted filtration efficiency of various face masks.
| Mask (brand) | Yoga band | % FFE (SD)a |
|---|---|---|
| N95 respirator (3M, 8210) | No | 85.3 (3.1) |
| Yes | 96.1 (0.6) | |
| % improvementb | +12.7 | |
| KF94 micro-dust protection mask (Dr Puri) | No | 61.9 (6.7) |
| Yes | 80.2 (3.8) | |
| % improvementb | +29.6 | |
| KN95 folding particle protection disposable mask (Lei Shi De) | No | 54.9 (7.9) |
| Yes | 65.7 (5.7) | |
| % improvementb | +19.8 | |
| Procedure mask, earloop (Medline Industries) | No | 30.6 (10.4) |
| Yes | 36.6 (7.7) | |
| % improvementb | +19.7 | |
| Cloth/cotton mask (Hanesbrands) | No | 39.4 (7.3) |
| Yes | 40.6 (8.0) | |
| % improvementb | +2.9 |
aThe efficiency (FFE) is calculated as [1 – (mask count/ambient count)] × 100 across the length of the test. The FFE ± SD are shown. The average of at least two unique tests is presented.
b% improvement was calculated as the percentage increase of FFE with and without the elastic band.