During the past 30 years, the enhancement of world’s economic came up with a critical problem which is air pollutions. Major primary pollutants produced by human activity include: carbon dioxide (CO2), sulfur oxides (SOx), particulate matters, etc. There was a review showed that long-term exposure to PM2.5 (fine particulates) will increases the overall risk of non-accidental mortality from lung cancer by 15% to 21% per 10 ug/m3 increase. Therefor, high quality of facemask which could obstruct fine particulates may effectively protect human from fine particulates. In this project, two different facemasks which randomly chosen from Amazon will used as the target to inspect the ability of particulates’ obstruction. SEM will be the main technology to detect the particles on or inside the facemasks.