I-EN 149 iyindinganiso yaseYurophu yokuhlola kanye nezidingo zokumaka zokuhlunga imaski ewuhhafu.Izifihla-buso ezinjalo zivala ikhala, umlomo nesilevu futhi zingase zibe namavalvu okuphefumulayo kanye/noma okukhipha umoya.I-EN 149 ichaza amakilasi amathathu anjalo imaski eyingxenye yezinhlayiyana, ebizwa ngokuthi i-FFP1, i-FFP2 ne-FFP3, (lapho i-FFP imele ukuhlunga ubuso) ngokuya ngokusebenza kahle kokuhlunga.Iphinde ihlukanise imaski ibe 'ukusetshenziswa kweshifu eyodwa kuphela' (ayiphinde isetshenziswe, imakwe ngokuthi i-NR) noma 'ingasetshenziswa kabusha (i-shift engaphezu kweyodwa)' (imakwe ngo-R), kanye nohlamvu olungeziwe lokumaka D lubonisa ukuthi imaski idlulile ukuhlolwa kokuvinjelwa kokuzikhethela usebenzisa uthuli lwe-dolomite.Izihlungi ezinjalo zokuphefumula zivikela ekuhogeleni izinhlayiya ezinjengezinhlayiya zothuli, amaconsi, nama-aerosol.
