Center of Excellence for Protective Equipment and Materials (CEPEM), 1280 Main St. W., Hamilton, ON, Canada
Siv qhov txuas hauv qab no los qhia tag nrho cov ntawv nyeem ntawm kab lus no nrog koj cov phooj ywg thiab cov npoj yaig.kawm ntxiv.
Cov koom haum saib xyuas kev noj qab haus huv tau pom zoo kom cov zej zog siv lub qhov ncauj qhov ntswg los txo qis kev kis kab mob hauv huab cua xws li COVID-19.Thaum lub npog ntsej muag ua raws li cov lim dej ua tau zoo, kev sib kis ntawm tus kab mob yuav raug txo kom tsawg, yog li nws yog ib qho tseem ceeb rau kev ntsuam xyuas particle filtration efficiency (PFE) ntawm lub npog ntsej muag.Txawm li cas los xij, cov nqi siab thiab cov sij hawm ntev txhuas cuam tshuam nrog kev yuav lub tshuab PFE turnkey los yog ntiav ib lub chaw kuaj pom zoo cuam tshuam rau kev kuaj cov ntaub ntawv lim.Nws yog qhov yuav tsum tau ua kom pom tseeb rau qhov kev xeem "kev cai" PFE;Txawm li cas los xij, ntau yam qauv uas sau ntawv PFE kuaj ntawm (kev kho mob) lub qhov ncauj qhov ntswg (piv txwv li, ASTM International, NIOSH) sib txawv heev hauv qhov tseeb ntawm lawv cov kev cai thiab cov lus qhia.Ntawm no, kev txhim kho ntawm "sab hauv" PFE system thiab cov txheej txheem rau kev kuaj lub qhov ncauj qhov ntswg hauv cov ntsiab lus ntawm cov qauv npog ntsej muag kho mob tam sim no tau piav qhia.Raws li ASTM thoob ntiaj teb cov qauv, lub kaw lus siv latex spheres (0.1 µm nominal size) aerosols thiab siv lub laser particle analyzer ntsuas particle concentration upstream thiab downstream ntawm daim npog qhov ncauj.Ua qhov ntsuas PFE ntawm ntau hom ntaub thiab lub ntsej muag kho mob.Cov txheej txheem tau piav qhia hauv txoj haujlwm no ua tau raws li cov qauv tam sim no ntawm kev sim PFE, thaum muab kev hloov pauv hloov pauv cov kev xav tau thiab kev lim dej.
Cov koom haum saib xyuas kev noj qab haus huv tau pom zoo kom cov pej xeem sawv daws hnav lub qhov ncauj qhov ntswg txhawm rau txwv kev kis tus kab mob COVID-19 thiab lwm yam kab mob tee dej thiab kab mob aerosol.[1] Qhov yuav tsum tau hnav lub qhov ncauj qhov ntswg yog qhov ua tau zoo hauv kev txo qis kev sib kis, thiab [2] qhia tias lub ntsej muag tsis zoo hauv zej zog muab kev lim dej zoo.Qhov tseeb, cov qauv kev tshawb fawb tau pom tias qhov txo qis hauv kev sib kis ntawm COVID-19 yuav luag sib npaug rau cov khoom sib xyaw ua haujlwm ntawm lub npog ntsej muag thiab kev txais yuav tus nqi, thiab cov kev ntsuas no thiab lwm cov pej xeem muaj kev sib koom ua ke hauv kev txo cov tsev kho mob thiab kev tuag.[3]
Tus naj npawb ntawm daim npog ntsej muag kho mob thiab lub tshuab ua pa uas xav tau los ntawm kev saib xyuas kev noj qab haus huv thiab lwm cov neeg ua haujlwm pem hauv ntej tau nce ntau, ua rau muaj kev sib tw rau cov khoom lag luam thiab cov khoom lag luam uas twb muaj lawm, thiab ua rau cov tuam txhab tshiab sim sai thiab lees paub cov ntaub ntawv tshiab.Cov koom haum xws li ASTM International thiab National Institute of Occupational Safety and Health (NIOSH) tau tsim cov txheej txheem rau kev kuaj lub ntsej muag kho mob;Txawm li cas los xij, cov ntsiab lus ntawm cov txheej txheem no sib txawv, thiab txhua lub koom haum tau tsim nws cov qauv kev ua tau zoo.
Piculate filtration efficiency (PFE) yog tus yam ntxwv tseem ceeb tshaj plaws ntawm lub npog ntsej muag vim nws muaj feem xyuam nrog nws lub peev xwm los lim cov khoom me me xws li aerosols.Lub npog ntsej muag kho mob yuav tsum ua kom tau raws li lub hom phiaj PFE [4-6] txhawm rau kom tau txais ntawv pov thawj los ntawm cov koom haum tswj hwm xws li ASTM International lossis NIOSH.Lub npog ntsej muag phais tau lees paub los ntawm ASTM, thiab N95 lub tshuab ua pa tau lees paub los ntawm NIOSH, tab sis ob lub qhov ncauj qhov ntswg yuav tsum dhau qhov tshwj xeeb PFE txiav tawm qhov tseem ceeb.Piv txwv li, N95 qhov ncauj qhov ntswg yuav tsum ua tiav 95% pom rau aerosols uas muaj cov ntsev ntsev nrog suav qhov nruab nrab txoj kab uas hla ntawm 0.075 µm, thaum ASTM 2100 L3 qhov ncauj qhov ntswg phais yuav tsum ua tiav 98% pom rau aerosols muaj li ntawm cov pob yas nrog qhov nruab nrab ntawm 0.1 µm. .
Thawj ob txoj kev xaiv yog kim (> $ 1,000 rau ib qho qauv kuaj, kwv yees li> $ 150,000 rau cov khoom siv tshwj xeeb), thiab thaum lub sijhawm COVID-19 muaj kev sib kis, muaj kev ncua vim lub sijhawm xa khoom ntev thiab teeb meem khoom.Tus nqi siab ntawm kev kuaj PFE thiab txwv tsis pub nkag mus rau cov cai - suav nrog qhov tsis muaj kev qhia sib koom ua ke ntawm cov qauv ntsuas kev ua tau zoo - tau coj cov kws tshawb fawb los siv ntau yam kev ntsuas kev kho mob, uas feem ntau ua raws li ib lossis ntau tus qauv rau daim npog qhov ncauj qhov ntswg kho mob.
Cov khoom siv npog ntsej muag tshwj xeeb kuaj pom hauv cov ntaub ntawv uas twb muaj lawm feem ntau zoo ib yam li NIOSH los yog ASTM F2100 / F2299 cov qauv saum toj no.Txawm li cas los xij, cov kws tshawb fawb muaj lub sijhawm los xaiv lossis hloov cov qauv tsim lossis kev ua haujlwm raws li lawv nyiam.Piv txwv li, kev hloov pauv ntawm cov qauv saum npoo av, huab cua / aerosol flow rate, qauv loj (chaw), thiab aerosol particle muaj pes tsawg leeg tau siv.Ntau qhov kev tshawb fawb tsis ntev los no tau siv cov cuab yeej siv los ntsuas cov ntaub ntawv npog.Cov khoom siv no siv sodium chloride aerosols thiab ze rau NIOSH cov qauv.Piv txwv li, Rogak et al.(2020), Zangmeister et al.(2020), Drunic et al.(2020) and Joo et al.(2021) Tag nrho cov cuab yeej tsim yuav tsim sodium chloride aerosol (ntau qhov ntau thiab tsawg), uas yog nruab nrab los ntawm cov nqi hluav taws xob, diluted nrog cov cua lim thiab xa mus rau cov khoom siv, qhov twg optical particle sizer, condensed particles ntawm ntau yam sib xyaw particle concentration ntsuas [9, 14-16] Konda et al.(2020) and Hao et al.(2020) Ib lub cuab yeej zoo sib xws tau tsim, tab sis tus nqi nruab nrab tsis suav nrog.[8, 17] Hauv cov kev tshawb fawb no, cov huab cua tshaj tawm hauv cov qauv sib txawv ntawm 1 thiab 90 L min-1 (qee zaum txhawm rau txheeb xyuas cov dej ntws / nrawm);Txawm li cas los xij, qhov nrawm nrawm yog nruab nrab ntawm 5.3 thiab 25 cm s-1 nruab nrab.Tus qauv loj zoo li txawv ntawm ≈3.4 thiab 59 cm2.
Ntawm qhov tsis sib xws, muaj qee qhov kev tshawb fawb txog kev ntsuam xyuas cov ntaub ntawv npog ntsej muag los ntawm cov khoom siv latex aerosol, uas yog ze rau ASTM F2100 / F2299 tus qauv.Piv txwv li, Bagheri et al.(2021), Shakya et al.(2016) and Lu et al.(2020) Tsim ib lub cuab yeej los tsim cov polystyrene latex aerosol, uas tau diluted thiab xa mus rau cov khoom kuaj, qhov twg ntau yam particle analyzers los yog scanning txav particle loj analyzers tau siv los ntsuas particle concentration.[18-20] Lu et al.Tus nqi nruab nrab tau siv qis qis ntawm lawv lub tshuab hluav taws xob aerosol, thiab cov kws sau ntawv ntawm lwm qhov kev tshawb fawb tsis tau.Cov huab cua ntws hauv cov qauv kuj hloov me ntsis - tab sis nyob rau hauv qhov txwv ntawm F2299 tus qauv - los ntawm ≈7.3 txog 19 L min-1.Cov huab cua nto nrawm kawm los ntawm Bagheri li al.yog 2 thiab 10 cm s–1 (nyob rau hauv tus qauv ntau), feem.Thiab Lu et al., thiab Shakya et al.[18-20] Tsis tas li ntawd, tus sau thiab Shakya li al.kuaj latex spheres ntawm ntau qhov ntau thiab tsawg (ie, tag nrho, 20 nm txog 2500 nm).Thiab Lu et al.Yam tsawg kawg hauv qee qhov ntawm lawv qhov kev sim, lawv siv qhov ntsuas 100 nm (0.1 µm) particle loj.
Hauv kev ua haujlwm no, peb piav qhia txog cov teeb meem uas peb ntsib hauv kev tsim cov cuab yeej PFE uas ua raws li cov qauv ASTM F2100 / F2299 uas twb muaj lawm ntau npaum li qhov ua tau.Ntawm cov qauv nrov tseem ceeb (piv txwv li NIOSH thiab ASTM F2100 / F2299), ASTM tus qauv muab kev hloov pauv ntau dua hauv qhov ntsuas (xws li huab cua ntws tus nqi) los kawm txog kev lim dej uas yuav cuam tshuam rau PFE hauv cov qhov ncauj qhov ntswg uas tsis yog tshuaj kho mob.Txawm li cas los xij, raws li peb tau pom, qhov kev hloov pauv no muab ib theem ntxiv ntawm kev nyuaj hauv kev tsim cov cuab yeej zoo li no.
Cov tshuaj tau yuav los ntawm Sigma-Aldrich thiab siv raws li yog.Styrene monomer (≥99%) yog purified los ntawm ib lub iav kem uas muaj alumina inhibitor tshem tawm, uas yog tsim los tshem tawm tert-butylcatechol.Deionized dej (≈0.037 µS cm–1) los ntawm Sartorius Arium dej purification system.
100% paj rwb tiaj weave (Muslin CT) nrog lub nominal hnyav ntawm 147 gm-2 los ntawm Veratex Lining Ltd., QC, thiab xyoob / spandex blend los ntawm D. Zinman Textiles, QC.Lwm cov ntaub ntawv npog ntsej muag yog los ntawm cov khw muag khoom hauv zos (Fabricland).Cov ntaub ntawv no suav nrog ob qhov sib txawv 100% paj rwb woven fabrics (nrog sib txawv prints), ib tug paj rwb / spandex knitted fabrics, ob paj rwb / polyester knitted fabrics (ib "universal" thiab ib "sweater fabric") thiab ib tug non-woven paj rwb / polypropylene blended. paj rwb batting khoom.Table 1 qhia txog cov ntsiab lus ntawm cov khoom paub ntaub.Txhawm rau txhawm rau ntsuas cov cuab yeej tshiab, daim ntawv pov thawj kho mob lub qhov ncauj qhov ntswg tau txais los ntawm cov tsev kho mob hauv zos, suav nrog ASTM 2100 Qib 2 (L2) thiab Qib 3 (L3; Halyard) tau lees paub lub ntsej muag kho mob thiab N95 lub tshuab ua pa (3M).
Ib qho qauv ncig ntawm kwv yees li 85 hli txoj kab uas hla tau txiav los ntawm txhua yam khoom siv los kuaj;tsis muaj kev hloov kho ntxiv rau cov khoom siv (piv txwv li, ntxuav).Clamp cov ntaub voj nyob rau hauv tus qauv tuav ntawm PFE ntaus ntawv rau kev sim.Qhov tseeb txoj kab uas hla ntawm tus qauv nyob rau hauv kev sib cuag nrog cov huab cua ntws yog 73 hli, thiab cov khoom seem yog siv los kho cov qauv nruj nreem.Rau lub ntsej muag sib dhos, sab uas kov lub ntsej muag yog nyob deb ntawm aerosol ntawm cov khoom siv.
Synthesis ntawm monodisperse anionic polystyrene latex spheres los ntawm emulsion polymerization.Raws li cov txheej txheem tau piav qhia hauv txoj kev tshawb fawb yav dhau los, cov tshuaj tiv thaiv tau ua nyob rau hauv ib nrab-batch hom ntawm monomer starvation.[21, 22] Ntxiv dej deionized (160 mL) rau 250 mL peb-caj dab puag ncig hauv qab khob thiab muab tso rau hauv ib lub dab da dej.Tom qab ntawd lub raj mis tau purged nrog nitrogen thiab inhibitor-free styrene monomer (2.1 mL) tau ntxiv rau lub purged, stirred flask.Tom qab 10 feeb ntawm 70 ° C, ntxiv sodium lauryl sulfate (0.235 g) yaj hauv dej deionized (8 mL).Tom qab 5 feeb ntxiv, poov tshuaj persulfate (0.5 g) yaj hauv dej deionized (2 mL) ntxiv.Tshaj li 5 teev tom ntej no, siv lub twj tso kua mis kom maj mam txhaj tshuaj ntxiv inhibitor-free styrene (20 mL) rau hauv lub khob ntawm tus nqi ntawm 66 µL min-1.Tom qab cov tshuaj styrene ua tiav, cov tshuaj tiv thaiv tau tshwm sim rau lwm 17 teev.Tom qab ntawd lub khob tau qhib thiab txias kom xaus lub polymerization.Lub synthesized polystyrene latex emulsion tau dialyzed tawm tsam cov dej deionized hauv SnakeSkin dialysis tube (3500 Da molecular hnyav txiav tawm) rau tsib hnub, thiab cov dej deionized tau hloov txhua hnub.Tshem tawm cov emulsion los ntawm lub raj lim dej thiab muab tso rau hauv lub tub yees ntawm 4 ° C kom txog thaum siv.
Dynamic light scattering (DLS) tau ua nrog Brookhaven 90Plus analyzer, lub laser wavelength yog 659 nm, thiab lub kaum sab xis detector yog 90 °.Siv cov khoom siv hauv cov khoom siv hauv particle daws teeb meem (v2.6; Brookhaven Instruments Corporation) los tshuaj xyuas cov ntaub ntawv.Lub latex ncua kev kawm ntawv yog diluted nrog deionized dej kom txog thaum cov particle suav yog kwv yees li 500 txhiab suav ib ob (kcps).Qhov loj me me tau txiav txim siab yog 125 ± 3 nm, thiab tshaj tawm polydispersity yog 0.289 ± 0.006.
ZetaPlus zeta muaj peev xwm analyzer (Brookhaven Instruments Corp.) tau siv los ntsuas tus nqi ntawm zeta muaj peev xwm hauv theem tsom teeb pom kev tawg.Cov qauv tau npaj los ntawm kev ntxiv ib qho aliquot ntawm latex rau 5 × 10-3m NaCl tov thiab diluting lub latex ncua kev kawm ntawv dua kom ua tau ib tug particle suav kwv yees li 500 kcps.Tsib qhov kev ntsuas rov ua dua (txhua qhov suav nrog 30 khiav) tau ua, ua rau zeta muaj peev xwm tus nqi ntawm -55.1 ± 2.8 mV, qhov uas qhov yuam kev sawv cev rau tus qauv sib txawv ntawm tus nqi nruab nrab ntawm tsib qhov rov ua dua.Cov kev ntsuas no qhia tau hais tias cov khoom tsis zoo raug them thiab tsim kom muaj kev ncua ruaj khov.DLS thiab zeta tej zaum cov ntaub ntawv tuaj yeem pom hauv cov ntaub ntawv txhawb nqa S2 thiab S3.
Peb tsim cov cuab yeej ua raws li ASTM International cov qauv, raws li tau piav qhia hauv qab no thiab pom hauv daim duab 1. Lub tshuab hluav taws xob ib leeg-jet Blaustein atomization (BLAM; CHTech) aerosol generator yog siv los tsim cov aerosols uas muaj cov khoom siv roj hmab.Cov cua lim dej (tau txais los ntawm GE Healthcare Whatman 0.3 µm HEPA-CAP thiab 0.2 µm POLYCAP TF lim hauv series) nkag mus rau lub tshuab hluav taws xob aerosol ntawm lub siab ntawm 20 psi (6.9 kPa) thiab atomizes ib feem ntawm 5 mg L-1 Kev ncua Cov kua yog txhaj rau hauv lub pob latex ntawm cov khoom siv los ntawm lub twj tso kua mis syringe (KD Scientific Model 100).Cov khoom ntub dej aerosolized yog qhuav los ntawm kev hla cov cua tawm hauv lub tshuab hluav taws xob aerosol los ntawm lub tubular kub exchanger.Lub tshav kub exchanger muaj 5/8 " stainless hlau raj qhov txhab nrog 8-foot-ntev cua sov kauj.Cov zis yog 216 W (BriskHeat).Raws li nws cov adjustable dial, lub tso zis tso cua sov yog teem rau 40% ntawm tus nqi siab tshaj plaws ntawm lub cuab yeej (≈86 W);qhov no ua rau qhov nruab nrab sab nrauv phab ntsa kub ntawm 112 ° C (tus qauv sib txawv ≈1 ° C), uas yog txiav txim siab los ntawm kev ntsuas qhov ntsuas kub ntawm qhov chaw (Taylor USA).Daim duab S4 hauv cov ntaub ntawv txhawb nqa qhia txog kev ua haujlwm ntawm lub tshuab cua sov.
Cov khoom atomized qhuav yog tom qab ntawd tov nrog lub ntim loj ntawm cov cua lim kom ua tiav tag nrho cov cua ntws ntawm 28.3 L min-1 (uas yog, 1 cubic feet ib feeb).Tus nqi no tau raug xaiv vim tias nws yog qhov tseeb txaus ntawm lub laser particle analyzer ntsuas ntsuas qis qis ntawm qhov system.Cov huab cua nqa cov khoom latex raug xa mus rau ib qho ntawm ob chav ntsug zoo tib yam (xws li cov phab ntsa zoo nkauj stainless hlau): lub "tswj" chamber tsis muaj cov khoom siv npog ntsej muag, lossis lub voj voog-txiav "cov qauv" chamber-siv detachable Tus qauv tuav yog ntxig rau sab nraum cov ntaub.Sab hauv txoj kab uas hla ntawm ob chav yog 73 hli, uas phim lub puab txoj kab uas hla ntawm tus qauv tuav.Tus qauv tuav siv cov grooved rings thiab recessed bolts kom nruj cov khoom siv lub npog ntsej muag, thiab tom qab ntawd ntxig lub bracket detachable rau hauv qhov sib txawv ntawm cov qauv chamber, thiab kaw nws nruj nreem rau hauv cov cuab yeej nrog roj hmab gaskets thiab clamps (Daim duab S2, cov ntaub ntawv txhawb nqa).
Txoj kab uas hla ntawm cov qauv ntaub nyob rau hauv kev sib cuag nrog airflow yog 73 hli (chaw = 41.9 cm2);nws raug kaw nyob rau hauv cov qauv chamber thaum lub sij hawm xeem.Cov cua ntws tawm ntawm lub "tswj" lossis "cov qauv" chamber raug xa mus rau lub laser particle analyzer (particle ntsuas qhov system LASAIR III 110) los ntsuas tus naj npawb thiab cov ntsiab lus ntawm cov latex.Cov particle analyzer qhia qhov qis thiab sab sauv txwv ntawm particle concentration, raws li 2 × 10-4 thiab ≈34 particles ib cubic feet (7 thiab ≈950 000 particles ib cubic feet).Rau kev ntsuas ntawm latex particle concentration, particle concentration yog qhia nyob rau hauv ib tug "lub thawv" nrog ib tug qis dua thiab ib tug siab txwv ntawm 0.10-0.15 µm, sib xws rau kwv yees qhov loj ntawm singlet latex particles nyob rau hauv lub aerosol.Txawm li cas los xij, lwm qhov ntau thiab tsawg tuaj yeem siv tau, thiab ntau lub bins tuaj yeem ntsuas tib lub sijhawm, nrog qhov siab tshaj plaws ntawm 5 µm.
Cov khoom siv kuj suav nrog lwm yam khoom siv, xws li cov cuab yeej siv rau kev tso dej tawm hauv chamber thiab particle analyzer nrog cov huab cua huv huv, nrog rau cov khoom siv thiab cov cuab yeej tsim nyog (Daim duab 1).Daim duab qhia txog cov kav dej thiab ntsuas ntsuas tau pom hauv daim duab S1 thiab Table S1 ntawm cov ntaub ntawv txhawb nqa.
Thaum lub sij hawm kev sim, cov latex ncua kev kawm ntawv tau txhaj rau hauv lub tshuab hluav taws xob aerosol ntawm tus nqi ntws ntawm ≈60 mus rau 100 µL min-1 kom muaj qhov ruaj khov particle tso tawm, kwv yees li 14-25 particles ib cubic centimeter (400 000-ib cubic centimeter) 700 000 particle).Ko taw) nyob rau hauv ib lub thawv nrog qhov loj ntawm 0.10-0.15 µm.Qhov kev khiav dej num no yog qhov yuav tsum tau vim yog qhov kev hloov pauv hauv cov ntsiab lus ntawm cov khoom siv latex downstream ntawm lub tshuab hluav taws xob aerosol, uas tej zaum yuav raug ntaus nqi los ntawm kev hloov pauv ntawm cov latex ncua kev ntes los ntawm cov kua ntxiab ntawm lub tshuab hluav taws xob aerosol.
Txhawm rau ntsuas PFE ntawm cov qauv ntaub, cov latex particle aerosol yog thawj zaug xa mus rau hauv chav tswj thiab tom qab ntawd xa mus rau cov khoom ntsuas particle.Tsis tu ncua ntsuas qhov concentration ntawm peb cov khoom hauv kev ua tiav sai, txhua lub sijhawm ib feeb.Tus neeg soj ntsuam particle qhia lub sij hawm nruab nrab ntawm cov ntsiab lus thaum lub sij hawm ntsuam xyuas, uas yog, qhov nruab nrab concentration ntawm hais nyob rau hauv ib feeb (28.3 L) ntawm cov qauv.Tom qab siv cov kev ntsuas hauv qab no los tsim kom muaj qhov ruaj khov particle suav thiab roj ntws tus nqi, cov aerosol raug xa mus rau cov qauv chamber.Thaum lub kaw lus nce mus txog qhov sib npaug (feem ntau yog 60-90 vib nas this), qhov ntsuas peb zaug sib law liag ib feeb tau ua tiav sai.Cov qauv ntsuas no sawv cev rau qhov concentration ntawm cov khoom uas dhau los ntawm cov qauv ntaub.Tom qab ntawd, los ntawm kev faib cov aerosol ntws rov qab mus rau chav tswj, lwm qhov kev ntsuas peb qhov ntsuas particle tau raug coj los ntawm chav tswj xyuas kom paub tseeb tias cov dej ntws tawm qhov siab tsis tau hloov pauv ntau thaum lub sij hawm tag nrho cov qauv ntsuas txheej txheem.Txij li thaum tus qauv tsim ntawm ob chav chamber yog tib yam - tshwj tsis yog tias cov qauv chamber tuaj yeem ua raws li tus qauv coj mus kuaj - cov xwm txheej ntws hauv chamber tuaj yeem suav tias yog tib yam, yog li qhov concentration ntawm cov khoom hauv cov pa tawm hauv lub chamber tswj thiab cov qauv chamber. tau muab piv.
Txhawm rau kom tswj tau lub neej ntawm cov cuab yeej ntsuas particle thiab tshem tawm cov khoom aerosol hauv cov kab ke ntawm txhua qhov kev sim, siv HEPA lim cua dav hlau los ntxuav cov khoom ntsuas particle tom qab txhua qhov ntsuas, thiab ntxuav cov qauv chav ua ntej hloov cov qauv.Thov xa mus rau daim duab S1 hauv cov ntaub ntawv txhawb nqa rau daim duab schematic ntawm lub tshuab nqus dej ntawm lub tshuab PFE.
Qhov kev suav no sawv cev rau ib qho kev ntsuas "rov ua dua" PFE rau ib qho qauv ntawm cov khoom siv thiab sib npaug rau PFE suav hauv ASTM F2299 (Kev Sib Tw (2)).
Cov ntaub ntawv teev tseg hauv §2.1 tau sib tw nrog cov latex aerosols siv cov khoom siv PFE tau piav qhia hauv §2.3 los txiav txim lawv qhov tsim nyog raws li cov ntaub ntawv npog.Daim duab 2 qhia tau hais tias cov kev nyeem tau los ntawm particle concentration analyzer, thiab PFE qhov tseem ceeb ntawm sweater fabrics thiab batting cov ntaub ntawv yog ntsuas nyob rau tib lub sij hawm.Peb qhov kev ntsuam xyuas tau ua tiav rau tag nrho ob yam khoom thiab rau qhov rov ua dua.Pom tseeb, thawj qhov kev nyeem ntawv hauv ib pawg ntawm peb qhov kev nyeem ntawv (tso nrog cov xim sib dua) feem ntau txawv ntawm ob qhov kev nyeem ntawv.Piv txwv li, thawj qhov kev nyeem ntawv txawv ntawm qhov nruab nrab ntawm ob qhov kev nyeem ntawv hauv 12-15 triples hauv daim duab 2 los ntawm ntau dua 5%.Qhov kev soj ntsuam no muaj feem xyuam rau qhov sib npaug ntawm cov huab cua uas muaj aerosol uas ntws los ntawm cov particle analyzer.Raws li tau tham hauv Cov Khoom Siv thiab Cov Txheej Txheem, qhov sib npaug ntawm kev nyeem ntawv (qhov thib ob thiab thib peb kev tswj hwm thiab cov qauv nyeem) tau siv los xam PFE hauv cov xim xiav tsaus thiab xim liab hauv daim duab 2, feem.Zuag qhia tag nrho, qhov nruab nrab PFE tus nqi ntawm peb qhov replicates yog 78% ± 2% rau lub tsho ntaub thiab 74% ± 2% rau paj rwb batting khoom.
Txhawm rau ntsuas qhov ua tau zoo ntawm lub kaw lus, ASTM 2100 daim npog qhov ncauj qhov ntswg kho mob (L2, L3) thiab NIOSH lub tshuab ua pa (N95) kuj raug soj ntsuam.ASTM F2100 tus qauv teeb tsa cov sub-micron particle filtration efficiency ntawm 0.1 µm particles ntawm qib 2 thiab qib 3 qhov ncauj qhov ntswg kom ≥ 95% thiab ≥ 98%, feem.[5] Ib yam li ntawd, NIOSH-certified N95 respirators yuav tsum tau pom qhov ua tau zoo ntawm ≥95% rau atomized NaCl nanoparticles nrog qhov nruab nrab txoj kab uas hla ntawm 0.075 µm.[24] Rengasamy et al.Raws li cov lus ceeb toom, zoo li N95 lub qhov ncauj qhov ntswg qhia tus nqi PFE ntawm 99.84%–99.98%, [25] Zangmeister li al.Raws li cov lus ceeb toom, lawv cov N95 ua kom pom qhov tsawg kawg nkaus ntawm ntau dua 99.9%, [14] thaum Joo et al.Raws li cov lus ceeb toom, 3M N95 qhov ncauj qhov ntswg tsim 99% ntawm PFE (300 nm hais), [16] thiab Hao li al.Cov ntawv tshaj tawm N95 PFE (300 nm hais) yog 94.4%.[17] Rau ob lub ntsej muag N95 sib tw los ntawm Shakya li al.nrog 0.1 µm latex pob, PFE poob qis ntawm 80% thiab 100%.[19] Thaum Lu et al.Siv cov pob latex ntawm tib qhov loj los ntsuas N95 lub ntsej muag, qhov nruab nrab PFE tau tshaj tawm tias yog 93.8%.[20] Cov txiaj ntsig tau los ntawm kev siv cov cuab yeej siv tau piav qhia hauv txoj haujlwm no qhia tau tias PFE ntawm N95 daim npog ntsej muag yog 99.2 ± 0.1%, uas yog qhov pom zoo nrog feem ntau cov kev tshawb fawb yav dhau los.
Lub npog ntsej muag phais kuj tau sim hauv ntau qhov kev tshawb fawb.Lub ntsej muag phais ntawm Hao et al.pom PFE (300 nm particles) ntawm 73.4%, [17] thaum peb lub ntsej muag phais kuaj los ntawm Drewnick li al.PFE tsim muaj li ntawm kwv yees li 60% mus rau yuav luag 100%.[15] (Lub npog ntsej muag tom kawg yuav yog tus qauv muaj ntawv pov thawj.) Txawm li cas los xij, Zangmeister li al.Raws li cov lus ceeb toom, qhov tsawg kawg nkaus pom kev ua tau zoo ntawm ob lub qhov ncauj qhov ntswg kuaj tau tsuas yog siab dua me ntsis ntau dua 30%, [14] qis dua qhov kev phais qhov ncauj qhov ntswg kuaj hauv txoj kev tshawb no.Ib yam li ntawd, "blue surgical mask" tested by Joo et al.Ua pov thawj tias PFE (300 nm hais) tsuas yog 22%.[16] Shakya et al.tau tshaj tawm tias PFE ntawm qhov ncauj qhov ntswg phais (siv 0.1 µm latex particles) txo qis los ntawm 60-80%.[19] Siv cov khoom latex ntawm tib qhov loj, Lu li al.'s surgical daim npog qhov ncauj ua rau PFE qhov nruab nrab ntawm 80.2%.[20] Hauv kev sib piv, PFE ntawm peb lub npog ntsej muag L2 yog 94.2 ± 0.6%, thiab PFE ntawm L3 daim npog qhov ncauj yog 94.9 ± 0.3%.Txawm hais tias cov PFEs no dhau ntau PFEs hauv cov ntaub ntawv, peb yuav tsum nco ntsoov tias yuav luag tsis muaj cov ntawv pov thawj tau hais hauv kev tshawb fawb yav dhau los, thiab peb lub ntsej muag phais tau txais qib 2 thiab qib 3 daim ntawv pov thawj.
Ib yam li cov neeg sib tw daim npog ntsej muag cov ntaub ntawv hauv daim duab 2 tau soj ntsuam, peb qhov kev sim tau ua rau lwm yam rau 6 cov ntaub ntawv los txiav txim lawv qhov tsim nyog hauv daim npog ntsej muag thiab ua kom pom kev ua haujlwm ntawm PFE ntaus ntawv.Daim duab 3 qhia txog PFE qhov tseem ceeb ntawm tag nrho cov khoom siv kuaj thiab muab piv nrog PFE qhov tseem ceeb tau txais los ntawm kev soj ntsuam cov ntaub ntawv pov thawj L3 thiab N95 daim npog ntsej muag.Los ntawm 11 lub qhov ncauj qhov ntswg / tus neeg sib tw daim npog ntsej muag xaiv rau txoj haujlwm no, ntau yam ntawm PFE kev ua tau zoo tuaj yeem pom tau meej, txij li ≈10% mus rau 100%, zoo ib yam nrog rau lwm yam kev tshawb fawb, [8, 9, 15] thiab cov neeg piav qhia kev lag luam Tsis muaj kev sib raug zoo ntawm PFE thiab PFE.Piv txwv li, cov ntaub ntawv uas muaj cov khoom zoo sib xws (ob lub 100% paj rwb qauv thiab paj rwb muslin) muaj qhov sib txawv PFE qhov tseem ceeb (14%, 54%, thiab 13%, feem).Tab sis nws yog ib qho tseem ceeb uas kev ua haujlwm qis (piv txwv li, 100% paj rwb A; PFE ≈ 14%), kev ua haujlwm nruab nrab (piv txwv li, 70% / 30% paj rwb / polyester sib xyaw; PFE ≈ 49%) thiab kev ua haujlwm siab (piv txwv li, Sweater Fabric; PFE ≈ 78%) Cov ntaub tuaj yeem txheeb xyuas kom meej siv cov khoom siv PFE tau piav qhia hauv txoj haujlwm no.Tshwj xeeb tshaj yog sweater fabrics thiab paj rwb batting cov ntaub ntawv ua tau zoo heev, nrog PFEs li ntawm 70% mus rau 80%.Cov ntaub ntawv ua tau zoo li no tuaj yeem txheeb xyuas thiab txheeb xyuas kom ntxaws ntxiv kom nkag siab txog cov yam ntxwv uas ua rau lawv qhov kev ua haujlwm siab pom.Txawm li cas los xij, peb xav kom nco ntsoov tias vim tias PFE cov txiaj ntsig ntawm cov ntaub ntawv nrog cov lus piav qhia kev lag luam zoo sib xws (piv txwv li cov ntaub ntawv paj rwb) sib txawv heev, cov ntaub ntawv no tsis qhia tias cov ntaub ntawv twg muaj txiaj ntsig zoo rau daim npog ntsej muag, thiab peb tsis npaj siab los txiav txim siab cov khoom- pawg khoom.Kev sib raug zoo ntawm kev ua haujlwm.Peb muab cov piv txwv tshwj xeeb los ua kom pom kev calibration, qhia tias qhov kev ntsuas npog tag nrho cov kev ua tau zoo pom, thiab muab qhov loj ntawm qhov ntsuas qhov yuam kev.
Peb tau txais cov txiaj ntsig ntawm PFE no los ua pov thawj tias peb cov cuab yeej muaj peev xwm ntsuas tau ntau yam, ua yuam kev tsawg, thiab piv nrog cov ntaub ntawv tau txais hauv cov ntaub ntawv.Piv txwv li, Zangmeister et al.Cov txiaj ntsig ntawm PFE ntawm ntau cov paj rwb woven (xws li "paj rwb 1-11") (89 txog 812 threads ib nti) tau tshaj tawm.Nyob rau hauv 9 ntawm 11 cov ntaub ntawv, qhov "tsawg kawg filtration efficiency" yog li ntawm 0% mus rau 25%;PFE ntawm lwm cov ntaub ntawv yog kwv yees li 32%.[14] Ib yam li ntawd, Konda et al.Cov ntaub ntawv PFE ntawm ob lub paj rwb (80 thiab 600 TPI; 153 thiab 152 gm-2) tau tshaj tawm.PFE nyob ntawm 7% mus rau 36% thiab 65% mus rau 85%, feem.Hauv kev kawm ntawm Drewnick li al., nyob rau hauv ib txheej paj rwb ntaub (xws li paj rwb, paj rwb knit, moleton; 139-265 TPI; 80-140 gm-2), qhov ntau ntawm cov khoom PFE yog li ntawm 10% mus rau 30%.Hauv kev kawm ntawm Joo et al., lawv 100% paj rwb cov ntaub ntawv muaj PFE ntawm 8% (300 nm hais).Bagheri et al.siv polystyrene latex hais txog 0.3 txog 0.5 µm.PFE ntawm 6 cov ntaub ntawv paj rwb (120-200 TPI; 136-237 gm-2) tau ntsuas, xws li 0% mus rau 20%.[18] Yog li, feem ntau ntawm cov ntaub ntawv no tau pom zoo nrog PFE cov txiaj ntsig ntawm peb peb cov paj rwb ntaub (xws li Veratex Muslin CT, Fabric Store Paj Rwb A thiab B), thiab lawv qhov nruab nrab pom kev ua tau zoo yog 13%, 14% thiab feem.54%.Cov txiaj ntsig no qhia tau tias muaj qhov sib txawv loj ntawm cov ntaub ntawv paj rwb thiab cov khoom siv uas ua rau siab PFE (ie Konda li al.'s 600 TPI paj rwb; peb cov paj rwb B) tsis to taub.
Thaum ua cov kev sib piv no, peb lees paub tias nws yog ib qho nyuaj rau nrhiav cov ntaub ntawv kuaj hauv cov ntaub ntawv uas muaj cov yam ntxwv zoo ib yam (piv txwv li, cov ntaub ntawv muaj pes tsawg leeg, xaws thiab knitting, TPI, qhov hnyav, thiab lwm yam) nrog cov ntaub ntawv kuaj hauv txoj kev tshawb no, thiab yog li ntawd tsis tuaj yeem muab piv ncaj qha.Tsis tas li ntawd, qhov sib txawv ntawm cov cuab yeej siv los ntawm cov kws sau ntawv thiab qhov tsis muaj qauv tsim ua rau nws nyuaj rau kev sib piv zoo.Txawm li cas los xij, nws yog qhov tseeb tias qhov kev ua tau zoo / kev sib raug zoo ntawm cov ntaub zoo tib yam tsis to taub zoo.Cov ntaub ntawv yuav raug soj ntsuam ntxiv nrog cov qauv, hloov tau yooj yim thiab txhim khu kev qha (xws li cov cuab yeej tau piav qhia hauv txoj haujlwm no) txhawm rau txiav txim siab cov kev sib raug zoo no.
Txawm hais tias muaj qhov ua yuam kev tag nrho (0-5%) ntawm ib qho kev rov ua dua (0-4%) thiab cov qauv tshuaj ntsuam xyuas hauv triplicate, cov khoom siv hauv txoj haujlwm no tau ua pov thawj tias yog ib qho cuab yeej zoo rau kev sim PFE ntawm ntau yam ntaub ntawv.Ordinary fabrics rau daim npog ntsej muag kho mob.Nws yog ib qho tsim nyog sau cia tias ntawm 11 cov ntaub ntawv uas tau sim rau daim duab 3, qhov kev nthuav tawm yuam kev σprop tshaj qhov kev sib txawv ntawm PFE ntsuas ntawm ib qho qauv, uas yog, σsd ntawm 9 tawm ntawm 11 cov ntaub ntawv;Ob qhov kev zam no tshwm sim hauv tus nqi PFE siab heev (piv txwv li L2 thiab L3 daim npog qhov ncauj).Txawm hais tias cov txiaj ntsig tau nthuav tawm los ntawm Rengasamy li al.Qhia tias qhov sib txawv ntawm cov qauv rov ua dua yog me me (piv txwv li, tsib qhov rov ua dua <0.29%), [25] lawv tau kawm cov ntaub ntawv nrog cov khoom siv lim dej uas paub zoo tsim tshwj xeeb rau kev tsim daim npog ntsej muag: cov khoom siv nws tus kheej yuav zoo ib yam, thiab qhov kev sim no kuj yog qhov no. thaj tsam ntawm PFE ntau yam yuav zoo ib yam.Zuag qhia tag nrho, cov txiaj ntsig tau txais los ntawm peb cov cuab yeej siv tau ua raws li PFE cov ntaub ntawv thiab cov qauv ntawv pov thawj tau txais los ntawm lwm cov kws tshawb fawb.
Txawm hais tias PFE yog qhov ntsuas tseem ceeb los ntsuas qhov kev ua tau zoo ntawm lub npog ntsej muag, ntawm lub sijhawm no peb yuav tsum nco ntsoov cov neeg nyeem tias kev tshuaj xyuas dav dav ntawm cov ntaub ntawv npog ntsej muag yav tom ntej yuav tsum xav txog lwm yam, uas yog, cov khoom siv permeability (uas yog, los ntawm kev poob siab lossis kev ntsuas siab sib txawv. ).Muaj cov kev cai hauv ASTM F2100 thiab F3502.Kev lees txais kev ua pa yog qhov tseem ceeb rau kev nplij siab ntawm tus neeg hnav thiab tiv thaiv kom tsis txhob tawm ntawm lub npog ntsej muag thaum ua pa.Txij li thaum PFE thiab huab cua permeability ntawm ntau cov khoom siv feem ntau yog qhov sib txawv, qhov ntsuas qhov poob siab yuav tsum tau ua ua ke nrog PFE ntsuas kom ntsuas qhov ua tau zoo ntawm cov khoom siv npog ntsej muag.
Peb pom zoo tias cov lus qhia rau kev tsim cov khoom siv PFE raws li ASTM F2299 yog qhov tseem ceeb rau kev txhim kho txuas ntxiv ntawm cov qauv, tsim cov ntaub ntawv tshawb fawb uas tuaj yeem sib piv ntawm cov chaw soj ntsuam kev tshawb fawb, thiab kev txhim kho aerosol pom.Tsuas yog tso siab rau NIOSH (lossis F3502) tus qauv, uas qhia txog ib qho khoom siv (TSI 8130A) thiab txwv tsis pub cov kws tshawb fawb los ntawm kev yuav khoom siv turnkey (piv txwv li, TSI systems).Kev cia siab rau cov txheej txheem txheej txheem xws li TSI 8130A yog qhov tseem ceeb rau cov qauv ntawv pov thawj tam sim no, tab sis nws txwv txoj kev txhim kho ntawm lub ntsej muag, lub tshuab ua pa, thiab lwm yam aerosol filtration technologies uas khiav tawm tsam kev tshawb fawb.Nws yog ib qho tsim nyog sau cia tias tus qauv NIOSH tau tsim los ua ib txoj hauv kev rau kev ntsuas lub tshuab ua pa nyob rau hauv cov xwm txheej hnyav uas xav tau thaum cov khoom siv no xav tau, tab sis qhov sib txawv, lub ntsej muag phais raug kuaj los ntawm ASTM F2100 / F2299 txoj kev.Cov duab thiab cov qauv ntawm lub qhov ncauj qhov ntswg hauv zej zog muaj ntau dua li lub ntsej muag phais, uas tsis tau txhais hais tias lawv muaj kev pom zoo ua haujlwm zoo li N95.Yog tias daim npog ntsej muag tseem raug soj ntsuam raws li ASTM F2100 / F2299, cov ntaub zoo tib yam yuav tsum tau soj ntsuam siv txoj hauv kev ze rau ASTM F2100 / F2299.Tsis tas li ntawd, ASTM F2299 tso cai rau kev hloov pauv ntxiv hauv qhov sib txawv (xws li huab cua ntws thiab qhov nrawm nrawm hauv cov kev tshawb fawb pom kev pom), uas yuav ua rau nws muaj peev xwm ua tau zoo tshaj plaws hauv kev tshawb fawb ib puag ncig.
Post lub sij hawm: Aug-30-2021