For the interest of reusing masks, this study tested used masks masks from AQBlue and Airphin. From a limited number of masks, used masks has a lower Removal efficiency (RE) about 74%, and after washing, the RE is about 82%. The new masks could achieve around 90%. The RE is considered as acceptable in compared to other masks in the market. The result is limited to used masks with 2-3 weeks wearing for daily commute and one wash. The study does not consider the RE to multiple washes or the effects of sanitization of washing.