What masks do medical staff wear when performing invasive operations?

Ordinary masks should be useless. A mask with good filterability and good sealing will do. Medical masks can be divided into ordinary masks and advanced masks. Ordinary medical masks are not expensive and the protection is not outstanding; Surgeons or dentists adopt advanced medical masks, which pay attention to the filtration of particles and the barrier of fluids, so as to ensure the breathability of wearing in a precise working environment. Haze refers to the haze caused by dust, sulfuric acid and nitric acid in the air. The difference between haze and fog is that the relative humidity is small when haze occurs, but it is saturated in fog (if there are a large number of condensation nuclei, the relative humidity may not reach 100%, and saturation may occur). Sources of toxic particulate matter in cities: firstly, automobile exhaust. Cars that use diesel have the highest emission standards. Medical masks imported from the United States, like Wei Xin, who works in Beijing, have good filterability, not only preventing particles, but also preventing droplets. When choosing a mask, you can look at the standard and filtration efficiency. You should be familiar with 3X brand N90 and N95 series masks, both of which are named after NIOSH standard. In addition to NIOSH standard, ASTM standard of American Society for Testing Materials, KN standard of China and FFP standard of Europe are all universal and can be used to measure important indicators of masks. Ordinary medical masks are relatively cheap and have poor protection, and are basically only suitable for ordinary nurses or cooking at home. Advanced medical masks are adopted by surgeons or dentists, who earn more and pay more attention to the quality of masks rather than the low cost. Advanced medical masks have excellent barrier to particles and liquids, ensuring breathability when worn in precise working environment. It can also deodorize. Sources of toxic particles in cities: first, automobile exhaust, medical masks imported from the United States, and Puwei server, which have good filterability and prevent both particles and fog drops. The filtration efficiency is 99.8% for particles as small as 0. 1 micron, and 99.9% for bacteria or virus carriers as small as 0.3 micron (common in droplets). SecureFit patented technology is adopted to adapt to different face shapes and achieve a high degree of fit. For the health of you and your family, wear a mask when you go out. I wish you happiness and hope to adopt it.