幫手pin下
口罩好多level同標示
最基本係睇VFE, BFE, PFE,效率愈高=最有用
BFE(Bacterial Filtration Efficiency)就是細菌過濾效率
PFE(Particle Filtration Efficiency)則是顆粒過濾效率
VFE( Virus Filtration Efficiency )從口罩過濾飛沫病毒微粒3.0 μm(微米)的微粒效率
最緊要係有齊bfe vfe ,缺一不可啊
當然歐美好多口罩無寫vfe,只係得astm lv,下面呢條link可以有更多detials
https://www.crosstex.com/sites/default/files/public/educational-resources/products-literature/guide20to20face20mask20selection20and20use20-202017.pdf