| Keywords |
KF94; Surgical N95; Quantitative fit testing; Fit factor; Total inward leakage |
| Abstract |
The purpose of this study was twofold: 1) to evaluate respirator fit factor (FF) and inward leakage (IL) of KF94 mask in two different designs (flat-fold, vertical-fold); and 2) to determine FF of KF94 mask when wearing using either ear-loop or headband clip in comparison with surgical N95 (SN95). A total of forty healthy participants were recruited for the present study. FF was measured according to the U.S. OSHA quantitative fit test protocol(CNC method) and IL was calculated from the measured FF while the physical activity was performed according to the Korean Ministry of Food and Drug Safety’s Total Inward Leakage test protocol. The results indicated a significant difference in FF and IL between different shapes of K94 in that flat-fold design has a better facial fit and thereby a lesser IL(FF= 5.35 ± 3.83, IL= 18.68 ± 8.70%) than vertical-fold design(FF=2.7 ± 1.46, IL = 33.21 ± 21.23%). In comparison with SN95, KF94 showed a significantly lesser FF(F=148.6, p<.001) with a noted difference between different shapes of SN95(flat-fold: 166.05 ± 38.21 vs. cup-shape: 133.20 ± 54.43). In terms of mask-wearing practice, a headband utilizing a headband clip significantly increased FF compared to mask-wearing with the earloop(p<.001).
In conclusion, mask FF and IL are significantly influenced by mask shape and harness design, and masks with higher FF result in lesser IL. Further, in terms of FF, SN95 outperformed KF94 in spite of similar filter performance. |