Daim npog N95 yog ib ntawm cuaj tus qauv tsim los ntawm NIOSH xyoo 1995. "N" txhais tau tias "tsis muaj kev tiv taus roj". "95" qhia tias raug rau tus naj npawb tshwj xeeb ntawm cov khoom kuaj sim siab, thiab cov concentration ntawm cov khoom me hauv daim npog yog 95% qis dua qhov concentration ntawm cov khoom seem ntawm sab nraud daim npog. 95% ntawm tus nqi no tsis yog qhov nruab nrab tab sis yam tsawg kawg nkaus.
Lwm qib NIOSH-lees paub cov khoom seem muaj xws li: N99, N100, R95, R99, R100, P95, P99, P100. Cov qib tiv thaiv no tiv thaiv ntau ntawm N95 tiv thaiv, qhov twg “R” txhais tau tias muaj roj lossis tsis muaj roj. Cov xwm txheej feem, yog tias siv rau kev tiv thaiv cov roj pleev rau qhov me me, kev siv lub sijhawm tsis pub ntau tshaj 8 teev; "P" txhais tau tias nws yog qhov tsim nyog rau roj lossis tsis muaj roj. Yog tias siv rau cov roj pleev rau qhov muaj feem me me, kev siv sijhawm yuav tsum ua raws li cov lus pom zoo ntawm cov khw. Thiab "99" thiab "100" xa mus rau qib uas pom kev ua haujlwm zoo, feem.
Raws li cov roj tawm tsam, nws muab faib ua "N", "R", thiab "P", thiab tau muab faib ua "95", "99", thiab "100" raws li tus nqi ntes. "R" txhais tau tias "tiv taus roj" thiab "P" txhais tau tias "ntawv pov thawj roj", thiab "99" hauv qhov piv ua piv tau tias 99% lossis ntau dua, thiab "100" txhais tau tias 99.7% lossis ntau dua.
Tsis tas li ntawd, thaum N100, P100, thiab R100 peb-hom qhov ncauj qhov ntswg tau kuaj nrog 0.3 micron hais, qhov thaiv kev ua haujlwm yuav tsum yog siab tshaj 99.7%, thiab cov lim N99, P99, thiab R99 yog tag nrho saum toj dua 99%, thaum N95, P95, thiab R95 yog txhua qhov lim. Ntau dua 95%.
Yog li no, daim npog N95 raug sim nrog 0.3 micron sodium chloride hais, thiab tus lej ntawm cov phom yuav tsum siab dua 95%. Thaum tus neeg hnav lub ntsej muag lub ntsej muag zoo nruj, nws xyuas kom cov cua nkag thiab tawm tau los ntawm lub npog ntsej muag nyob rau hauv qhov xwm txheej ntawm lub ntsej muag ze. N95 ntawv pov thawj tus naj npawb tau muab tawm tsuas yog ntsuas qhov kev ntsuas no tau ntsib. Feem ntau, cov qhov ncauj qhov ntswg tiv thaiv uas tau dhau daim qauv pov thawj hauv tebchaws tsis dhau N95 tus qauv.
