Maski a ffp3 otetezera ma virus ndi CE En 149 FFP3 opepuka nkhope nkhope chigoba amapangidwa ndi nsalu yoluka ya thonje yapamwamba kwambiri, maulusiwo ndiabwino komanso olimba, opatsa kuloleza kwabwino, mawonekedwe ofewa, omasuka, otetezeka pakhungu la nkhope komanso wopumira. ffp3 chigoba chopumira Mapangidwe apamwamba 4 a fyuluta yopangidwa ndi thonje yoluka imakhala ndi mpweya wabwino komanso mpweya wabwino m'malo otentha / achinyezi. Nsalu yofewa imagwiritsidwa ntchito zingwe zamakutu zomwe sizimapweteka makutu ngakhale zitakhala zazitali. Izi ffp3 chikho nkhope chigoba ndi vale amateteza pakamwa panu poteteza ku fumbi, malo owonongeka ndi mpweya, magalimoto utsi, ndi mpweya wamchenga. Ndiwo anti-fumbi ngakhale pakusintha kwanyengo.