Center of Excellence for Protective Equipment and Equipment (CEPEM), 1280 Main St. W., Hamilton, ON, Canada
Gwiritsani ntchito ulalo womwe uli pansipa kuti mugawane zolemba zonse za nkhaniyi ndi anzanu komanso anzanu.Dziwani zambiri.
Mabungwe azaumoyo aboma amalimbikitsa kuti anthu azigwiritsa ntchito masks kuti achepetse kufalikira kwa matenda obwera ndi ndege monga COVID-19.Chigoba chikagwira ntchito ngati fyuluta yogwira ntchito kwambiri, kufalikira kwa kachilomboka kumachepetsedwa, chifukwa chake ndikofunikira kuwunika magwiridwe antchito a particle filtration (PFE) a chigoba.Komabe, kukwera mtengo komanso nthawi yayitali yokhudzana ndi kugula makina a turnkey PFE kapena kubwereka labotale yovomerezeka zimalepheretsa kuyesa kwa zinthu zosefera.Pakufunikatu njira yoyesera ya PFE "yosinthidwa mwamakonda";komabe, miyezo yosiyana siyana yomwe imalimbikitsa kuyesa kwa PFE kwa masks (zachipatala) (mwachitsanzo, ASTM International, NIOSH) amasiyana kwambiri pofotokozera ndondomeko ndi malangizo awo.Apa, kupangidwa kwa "mkati" kachitidwe ka PFE ndi njira yoyesera masks malinga ndi miyezo yamakono yachipatala ikufotokozedwa.Malinga ndi miyezo yapadziko lonse ya ASTM, makinawa amagwiritsa ntchito ma aerosols a latex spheres (0.1 µm nominal size) ndipo amagwiritsa ntchito laser particle analyzer kuyeza kuchuluka kwa tinthu kumtunda ndi kumunsi kwa chigoba.Chitani miyeso ya PFE pansalu zosiyanasiyana wamba ndi masks azachipatala.Njira yomwe yafotokozedwera mu ntchitoyi ikugwirizana ndi zomwe zikuchitika pano pakuyesa kwa PFE, pomwe ikupereka kusinthasintha kuti igwirizane ndi zosowa ndi zosefera.
Mabungwe azaumoyo aboma amalimbikitsa kuti anthu wamba azivala masks kuti achepetse kufalikira kwa COVID-19 ndi matenda ena oyambitsidwa ndi madontho ndi aerosol.[1] Chofunikira kuvala masks ndichothandiza kuchepetsa kufala, ndipo [2] zikuwonetsa kuti masks osayesedwa ammudzi amapereka kusefa kothandiza.M'malo mwake, kafukufuku wachitsanzo awonetsa kuti kuchepetsedwa kwa kufalikira kwa COVID-19 kuli pafupifupi molingana ndi zomwe zimaphatikiziridwa bwino za chigoba komanso kuchuluka kwa kulera, ndipo izi ndi njira zina zokhudzana ndi kuchuluka kwa anthu zimathandizira kuchepetsa zipatala ndi kufa.[3]
Kuchuluka kwa masks ovomerezeka azachipatala ndi zopumira zomwe zimafunidwa ndi azaumoyo ndi ogwira ntchito ena akutsogolo kwawonjezeka kwambiri, zomwe zikubweretsa zovuta pakupanga ndi kugulitsa komwe kulipo, ndikupangitsa opanga atsopano kuyesa ndikutsimikizira zida zatsopano.Mabungwe monga ASTM International ndi National Institute of Occupational Safety and Health (NIOSH) apanga njira zokhazikika zoyezera masks azachipatala;komabe, tsatanetsatane wa njirazi zimasiyana mosiyanasiyana, ndipo bungwe lirilonse lakhazikitsa miyezo yake yoyendetsera ntchito.
Particulate filtration effectiveness (PFE) ndiye chinthu chofunikira kwambiri pa chigoba chifukwa chimagwirizana ndi kuthekera kwake kusefa tinthu ting'onoting'ono monga ma aerosols.Masks azachipatala ayenera kukwaniritsa zolinga za PFE[4-6] kuti atsimikizidwe ndi mabungwe olamulira monga ASTM International kapena NIOSH.Masks opangira opaleshoni amatsimikiziridwa ndi ASTM, ndipo zopumira za N95 zimatsimikiziridwa ndi NIOSH, koma masks onsewa ayenera kudutsa mfundo zodula za PFE.Mwachitsanzo, masks a N95 ayenera kukwaniritsa kusefera kwa 95% kwa ma aerosol opangidwa ndi tinthu tating'ono ta mchere towerengera pafupifupi mainchesi 0.075 µm, pomwe masks opangira opaleshoni ya ASTM 2100 L3 amayenera kusefera 98% ya ma aerosol opangidwa ndi mipira ya latex yokhala ndi pafupifupi 0.1 µm. .
Zosankha ziwiri zoyambirira ndizokwera mtengo (> $ 1,000 pachiyeso chilichonse, chomwe chikuyembekezeka kukhala > $ 150,000 pazida zomwe zatchulidwa), ndipo panthawi ya mliri wa COVID-19, pamakhala kuchedwa chifukwa cha nthawi yayitali yobweretsera komanso zovuta zoperekera.Mtengo wokwera wa kuyezetsa kwa PFE ndi ufulu wocheperako wopezeka - kuphatikiza ndi kusowa kwa chitsogozo chogwirizana pakuwunika koyenera kwa magwiridwe antchito - zapangitsa ofufuza kugwiritsa ntchito njira zosiyanasiyana zoyesera, zomwe nthawi zambiri zimatengera muyezo umodzi kapena ingapo ya masks ovomerezeka azachipatala.
Zida zapadera zoyezera zinthu za chigoba zomwe zimapezeka m'mabuku omwe alipo nthawi zambiri zimakhala zofanana ndi zomwe zatchulidwa pamwambapa za NIOSH kapena ASTM F2100/F2299.Komabe, ochita kafukufuku ali ndi mwayi wosankha kapena kusintha mapangidwe kapena magawo ogwiritsira ntchito malinga ndi zomwe amakonda.Mwachitsanzo, kusintha kwachitsanzo cha liwiro la pamwamba, kuthamanga kwa mpweya/aerosol, kukula kwa zitsanzo (malo), ndi kapangidwe ka tinthu ta aerosol tagwiritsidwa ntchito.Kafukufuku wambiri waposachedwa wagwiritsa ntchito zida zosinthidwa kuti aziwunika zida za chigoba.Zidazi zimagwiritsa ntchito ma aerosols a sodium chloride ndipo zili pafupi ndi miyezo ya NIOSH.Mwachitsanzo, Rogak et al.(2020), Zangmeister et al.(2020), Drunic et al.(2020) ndi Joo et al.(2021) Zida zonse zopangidwa zidzatulutsa sodium kolorayidi aerosol (zosiyanasiyana kukula kwake), zomwe sizimayendetsedwa ndi magetsi, zimachepetsedwa ndi mpweya wosefedwa ndikutumizidwa ku chitsanzo cha zinthu, kumene kuwala kwa tinthu ting'onoting'ono, tinthu tating'ono tating'ono tating'ono tating'ono tating'ono tating'onoting'ono [9] 14-16] Konda et al.(2020) ndi Hao et al.(2020) Chida chofananacho chidapangidwa, koma neutralizer ya charger sichinaphatikizidwe.[8, 17] M'maphunzirowa, kuthamanga kwa mpweya mu chitsanzocho kumasiyana pakati pa 1 ndi 90 L min-1 (nthawi zina kuti azindikire zotsatira zothamanga / kuthamanga);Komabe, kuthamanga kwapansi kunali pakati pa 5.3 ndi 25 cm s-1 pakati.Kukula kwachitsanzo kumawoneka kuti kumasiyana pakati pa ≈3.4 ndi 59 cm2.
M'malo mwake, pali kafukufuku wochepa pakuwunika kwa zida za chigoba kudzera pa zida zogwiritsira ntchito latex aerosol, yomwe ili pafupi ndi muyezo wa ASTM F2100/F2299.Mwachitsanzo, Bagheri et al.(2021), Shakya et al.(2016) ndi Lu et al.(2020) Anapanga chipangizo chopangira polystyrene latex aerosol, yomwe idachepetsedwa ndikutumizidwa ku zitsanzo zakuthupi, pomwe zowunikira zosiyanasiyana za tinthu kapena kusanthula kachulukidwe ka tinthu tating'onoting'ono zidagwiritsidwa ntchito kuyeza ndende ya tinthu.[18-20] Ndipo Lu et al.A neutralizer mlandu adagwiritsidwa ntchito kumunsi kwa jenereta yawo ya aerosol, ndipo olemba maphunziro ena awiri sanatero.Kuthamanga kwa mpweya mu chitsanzo kunasinthanso pang'ono-koma mkati mwa malire a F2299 standard-kuchokera ≈7.3 mpaka 19 L min-1.Kuthamanga kwapamwamba kwa mpweya wophunziridwa ndi Bagheri et al.ndi 2 ndi 10 cm s–1 (mkati mwa muyezo), motsatana.Ndipo Lu et al., ndi Shakya et al.[18-20] Kuphatikiza apo, wolemba ndi Shakya et al.kuyesedwa kwa latex magawo amitundu yosiyanasiyana (mwachitsanzo, 20 nm mpaka 2500 nm).ndi Lu et al.Osachepera m'mayeso awo ena, amagwiritsa ntchito kukula kwa tinthu tating'ono ta 100 nm (0.1 µm).
Mu ntchitoyi, tikufotokoza zovuta zomwe timakumana nazo popanga chipangizo cha PFE chomwe chimagwirizana ndi miyezo yomwe ilipo ya ASTM F2100/F2299 momwe tingathere.Pakati pa mfundo zazikuluzikulu zodziwika bwino (ie NIOSH ndi ASTM F2100/F2299), muyezo wa ASTM umapereka kusinthasintha kwakukulu mu magawo (monga kuchuluka kwa mpweya) kuti aphunzire momwe kusefa komwe kungakhudze PFE mu masks omwe siachipatala.Komabe, monga momwe tawonetsera, kusinthasintha kumeneku kumapereka mulingo wowonjezera wovuta popanga zida zotere.
Mankhwalawa adagulidwa ku Sigma-Aldrich ndipo amagwiritsidwa ntchito monga momwe zilili.Styrene monomer (≥99%) imayeretsedwa kudzera mugawo lagalasi lomwe lili ndi chochotsa cha alumina inhibitor, chomwe chimapangidwa kuti chichotse tert-butylcatechol.Madzi oyeretsedwa (≈0.037 µS cm-1) amachokera ku Sartorius Arium yoyeretsa madzi.
100% thonje plain weave (Muslin CT) yolemera mwadzina 147 gm-2 imachokera ku Veratex Lining Ltd., QC, ndipo kusakaniza kwansungwi/spandex kumachokera ku D. Zinman Textiles, QC.Zida zina zopangira chigoba zimachokera kwa ogulitsa nsalu zakomweko (Fabricland).Zidazi zimaphatikizapo nsalu ziwiri zosiyana za 100% za thonje (zosindikizidwa zosiyana), nsalu imodzi ya thonje / spandex, nsalu ziwiri za thonje / poliyesitala (imodzi "yapadziko lonse" ndi "nsalu ya sweta") ndi thonje / polypropylene yosakanizidwa. zinthu zomenyera thonje.Gulu 1 likuwonetsa chidule cha zinthu zodziwika za nsalu.Pofuna kuyika zida zatsopanozi, masks ovomerezeka azachipatala adapezedwa kuzipatala zakomweko, kuphatikiza ASTM 2100 Level 2 (L2) ndi Level 3 (L3; Halyard) masks ovomerezeka azachipatala ndi ma N95 respirators (3M).
Chitsanzo chozungulira cha pafupifupi 85 mm m'mimba mwake chinadulidwa kuchokera ku chinthu chilichonse kuti chiyesedwe;palibe zosintha zina zomwe zidapangidwa kuzinthu (mwachitsanzo, kutsuka).Gwirani lupu la nsalu mu chotengera chitsanzo cha chipangizo cha PFE kuti muyese.M'mimba mwake weniweni wa chitsanzo chokhudzana ndi kutuluka kwa mpweya ndi 73 mm, ndipo zipangizo zotsalira zimagwiritsidwa ntchito pokonza chitsanzocho mwamphamvu.Kwa chigoba chosonkhanitsidwa, mbali yomwe imakhudza nkhope ili kutali ndi aerosol ya zinthu zomwe zaperekedwa.
Kaphatikizidwe ka monodisperse anionic polystyrene latex spheres ndi emulsion polymerization.Malinga ndi ndondomeko yomwe yafotokozedwa mu phunziro lapitalo, zomwe zinachitikazo zinachitika mu theka-mtanda akafuna monomer njala.[21, 22] Onjezani madzi osungunula (160 mL) ku 250 mL botolo lapansi lozungulira la makosi atatu ndikuyiyika mu bafa loyambitsa mafuta.Botololo lidatsukidwa ndi nayitrogeni ndi styrene monomer (2.1 mL) wopanda inhibitor (2.1 mL) adawonjezedwa ku botolo lotsukidwa, logwedezeka.Pambuyo pa mphindi 10 pa 70 ° C, onjezerani sodium lauryl sulfate (0.235 g) wosungunuka m'madzi opanda madzi (8 mL).Pambuyo pa mphindi zisanu, potaziyamu persulfate (0.5 g) wosungunuka m'madzi osakanizidwa (2 ml) adawonjezeredwa.Pamaola asanu otsatirawa, gwiritsani ntchito pampu ya syringe kuti mubaya pang'onopang'ono styrene (20 mL) mu botolo pamlingo wa 66 µL min-1.Pambuyo kulowetsedwa kwa styrene kumalizidwa, zomwe zidachitika kwa maola ena 17.Kenako botolo anatsegulidwa ndi utakhazikika kuthetsa polymerization.Emulsion yopangidwa ndi polystyrene latex emulsion idasinthidwa motsutsana ndi madzi osungunuka mu chubu cha dialysis cha SnakeSkin (3500 Da molecular weight cut-cut) kwa masiku asanu, ndipo madzi osungunula adasinthidwa tsiku lililonse.Chotsani emulsion ku chubu cha dialysis ndikusunga mufiriji pa 4 ° C mpaka mugwiritse ntchito.
Dynamic light scattering (DLS) idachitidwa ndi Brookhaven 90Plus analyzer, laser wavelength inali 659 nm, ndipo chowunikira chinali 90 °.Gwiritsani ntchito pulogalamu yopangira tinthu tating'ono (v2.6; Brookhaven Instruments Corporation) kuti muwunike zambiri.Kuyimitsidwa kwa latex kumachepetsedwa ndi madzi a deionized mpaka chiwerengero cha tinthu chili pafupifupi 500 zikwi pa sekondi imodzi (kcps).The tinthu kukula anatsimikiza kukhala 125 ± 3 nm, ndipo ananena polydispersity anali 0.289 ± 0.006.
ZetaPlus zeta angathe analyzer (Brookhaven Instruments Corp.) anagwiritsidwa ntchito kuti apeze mtengo woyezera wa zeta zomwe zingatheke mu gawo lowunikira njira yobalalitsira kuwala.Chitsanzocho chinakonzedwa powonjezera aliquot ya latex ku yankho la 5 × 10-3m NaCl ndi kuchepetsa kuyimitsidwa kwa latex kachiwiri kuti mukwaniritse chiwerengero cha tinthu pafupifupi 500 kcps.Miyezo isanu yobwerezabwereza (iliyonse yomwe imakhala ndi maulendo a 30) inkachitidwa, zomwe zimapangitsa kuti zeta zikhale zamtengo wapatali -55.1 ± 2.8 mV, pomwe cholakwikacho chikuyimira kusokonezeka kwapakati pa chiwerengero cha kubwereza kasanu.Miyezo iyi ikuwonetsa kuti tinthu tating'onoting'ono tili ndi vuto loyipa ndikupanga kuyimitsidwa kokhazikika.DLS ndi zeta zomwe zingatheke zingapezeke m'magome othandizira S2 ndi S3.
Tinapanga zidazo motsatira miyezo ya ASTM International, monga momwe tafotokozera m'munsimu ndikuwonetsedwa mu Chithunzi 1. The single-jet Blaustein atomization module (BLAM; CHTech) jenereta ya aerosol imagwiritsidwa ntchito popanga ma aerosol omwe ali ndi mipira ya latex.Mpweya wosefedwa (wopezedwa kudzera mu GE Healthcare Whatman 0.3 µm HEPA-CAP ndi 0.2 µm POLYCAP TF zosefera motsatizana) zimalowa mu jenereta ya aerosol ndi mphamvu ya 20 psi (6.9 kPa) ndi kutulutsa atomize gawo la 5 mg L-1 kuyimitsidwa The madzi jekeseni mu mpira mpira wa zida kudzera syringe mpope (KD Scientific Model 100).The aerosolized chonyowa particles zouma podutsa mpweya mtsinje kusiya aerosol jenereta kudzera tubular kutentha exchanger.Chosinthira kutentha chimakhala ndi bala lachitsulo chosapanga dzimbiri la 5/8” chokhala ndi koyilo yotenthetsera yautali wa mapazi 8.Zotsatira zake ndi 216 W (BriskHeat).Malinga ndi kuyimba kwake kosinthika, kutulutsa kwa heater kumayikidwa ku 40% ya mtengo wapamwamba wa chipangizocho (≈86 W);izi zimapanga kutentha kwa kunja kwa khoma la 112 °C (kupotoka kokhazikika ≈1 °C), komwe kumatsimikiziridwa ndi muyeso wa thermocouple (Taylor USA) pamwamba.Chithunzi S4 mu chidziwitso chothandizira chikufotokozera mwachidule ntchito ya chotenthetsera.
The zouma atomized particles ndiye kusakaniza ndi voliyumu wokulirapo wa mpweya osasankhidwa kukwaniritsa okwana mpweya otaya mlingo wa 28.3 L min-1 (ndiko 1 kiyubiki phazi pa mphindi).Mtengowu udasankhidwa chifukwa ndi liwiro lolondola la chida cha laser particle analyzer kunsi kwa dongosolo.Mpweya womwe umanyamula tinthu ta latex umatumizidwa ku chimodzi mwa zipinda ziwiri zofanana (mwachitsanzo, machubu achitsulo chosapanga dzimbiri): chipinda "chowongolera" chopanda chigoba, kapena "chitsanzo" chogwiritsidwa ntchito mozungulira. amalowetsedwa kunja kwa nsalu.M'kati mwa zipinda ziwirizi ndi 73 mm, zomwe zimafanana ndi m'mimba mwake mwachitsanzo.Wogwirizirayo amagwiritsa ntchito mphete zopindika ndi ma bolts otsekeka kuti asindikize mwamphamvu chigobacho, kenako amayika bulaketi yomwe imatha kutsekeka pampata wa chipinda chachitsanzo, ndikusindikiza mwamphamvu mu chipangizocho ndi ma gaskets a rabara ndi zingwe (Chithunzi S2, zambiri zothandizira).
Kutalika kwa chitsanzo cha nsalu yokhudzana ndi mpweya ndi 73 mm (dera = 41.9 cm2);imasindikizidwa mu chipinda chachitsanzo panthawi yoyesedwa.Kuyenda kwa mpweya komwe kumachoka mu chipinda cha "control" kapena "chitsanzo" kumasamutsidwa ku laser particle analyzer (tinthu tating'onoting'ono tomwe timayesa LASAIR III 110) kuti muyese chiwerengero ndi kuchuluka kwa tinthu ta latex.The particle analyzer imatchula malire apansi ndi apamwamba a tinthu tating'onoting'ono, motsatira 2 × 10-4 ndi ≈34 particles pa phazi la kiyubiki (7 ndi ≈950 000 particles pa phazi la cubic).Pakuyezera kuchuluka kwa tinthu ta latex, kuchuluka kwa tinthu tating'onoting'ono kumanenedwa mu "bokosi" lomwe lili ndi malire otsika ndi malire apamwamba a 0.10-0.15 µm, molingana ndi kukula kwa singlet latex particles mu aerosol.Komabe, makulidwe ena a bin angagwiritsidwe ntchito, ndipo nkhokwe zingapo zitha kuyesedwa nthawi imodzi, ndi kukula kwakukulu kwa tinthu 5 µm.
Zidazi zimaphatikizanso zida zina, monga zida zothamangitsira chipinda ndi particle analyzer ndi mpweya woyeretsedwa bwino, komanso ma valve ndi zida zofunikira (Chithunzi 1).Zithunzi zonse za mapaipi ndi zida zikuwonetsedwa mu Chithunzi S1 ndi Table S1 pazothandizira.
Pa kuyesera, ndi lalabala kuyimitsidwa jekeseni mu jenereta aerosol pa otaya mlingo wa ≈60 kuti 100 µL min-1 kukhala khola tinthu linanena bungwe, pafupifupi 14-25 particles pa kiyubiki centimita (400 000-pa kiyubiki centimita) 700 000 zidutswa).Mapazi) mu bin yokhala ndi kukula kwa 0.10–0.15 µm.Kuthamanga kumeneku kumafunika chifukwa cha kusintha komwe kumawonekera kwa tinthu ta latex kumunsi kwa jenereta ya aerosol, zomwe zingabwere chifukwa cha kusintha kwa kuyimitsidwa kwa latex komwe kumagwidwa ndi msampha wamadzi wa jenereta ya aerosol.
Pofuna kuyeza PFE yachitsanzo cha nsalu yopatsidwa, aerosol ya latex imasamutsidwa kaye kudzera m'chipinda chowongolera kenako ndikuwongolera ku particle analyzer.Pitirizani kuyeza kuchuluka kwa tinthu tating'onoting'ono motsatizana motsatizana, chilichonse chimakhala ndi mphindi imodzi.The particle analyzer lipoti nthawi pafupifupi ndende ya particles pa kusanthula, ndiye kuti, pafupifupi ndende ya particles mu mphindi imodzi (28.3 L) ya chitsanzo.Mukatenga miyeso yoyambira iyi kuti mukhazikitse kuwerengera kokhazikika kwa tinthu ndi kuchuluka kwa gasi, aerosol imasamutsidwa kuchipinda chachitsanzo.Dongosolo likafika pamlingo (nthawi zambiri masekondi 60-90), miyeso ina itatu yotsatizana ya mphindi imodzi imatengedwa motsatizana.Miyezo iyi imayimira kuchuluka kwa tinthu tating'onoting'ono todutsa munsaluyo.Pambuyo pake, pogawaniza kutuluka kwa aerosol kubwerera kuchipinda chowongolera, miyeso ina itatu ya tinthu tating'ono idatengedwa kuchokera kuchipinda chowongolera kuti zitsimikizire kuti kumtunda kwa tinthu tating'ono sikunasinthe kwambiri panthawi yonse yowunika.Popeza mapangidwe a zipinda ziwirizi ndi zofanana-kupatulapo kuti chipinda chachitsanzo chingathe kutengera chitsanzo-mayendedwe a m'chipindamo amatha kuonedwa ngati ofanana, kotero kuchuluka kwa tinthu tating'onoting'ono mu gasi kumasiya chipinda chowongolera ndi chipinda chachitsanzo. tingayerekeze.
Kuti mukhalebe ndi moyo wa particle analyzer chida ndikuchotsa aerosol particles mu dongosolo pakati pa mayeso aliwonse, gwiritsani ntchito HEPA yosefedwa mpweya ndege kuyeretsa tinthu analyzer pambuyo muyeso uliwonse, ndi kuyeretsa chipinda chitsanzo musanasinthe zitsanzo.Chonde tchulani Chithunzi S1 muzambiri zothandizira kuti mupeze chithunzi cha makina otulutsa mpweya pa chipangizo cha PFE.
Kuwerengeraku kukuyimira muyeso umodzi wa PFE "wobwerezedwa" pazachitsanzo chimodzi ndipo ndi wofanana ndi kuwerengera kwa PFE mu ASTM F2299 (Equation (2)).
Zida zomwe zafotokozedwa mu §2.1 zidatsutsidwa ndi ma aerosol a latex pogwiritsa ntchito zida za PFE zomwe zafotokozedwa mu §2.3 kuti zitsimikizire kuyenerera kwawo ngati zida za chigoba.Chithunzi 2 chikuwonetsa zowerengera zomwe zapezedwa kuchokera ku particle concentration analyzer, ndipo mfundo za PFE za nsalu za sweti ndi zida zomenyera zimayesedwa nthawi imodzi.Kusanthula kwachitsanzo katatu kunachitika pazinthu ziwiri zonse ndi kubwereza kasanu ndi kamodzi.Mwachiwonekere, kuwerenga koyamba mumagulu atatu (okhala ndi mthunzi wopepuka) nthawi zambiri kumakhala kosiyana ndi kuwerengera kwina kuwiri.Mwachitsanzo, kuwerenga koyamba kumasiyana ndi kuchuluka kwa mawerengedwe ena awiri mu 12-15 katatu mu Chithunzi 2 ndi oposa 5%.Kuwonetsetsa uku kumagwirizana ndi kuchuluka kwa mpweya wokhala ndi aerosol womwe ukudutsa mu particle analyzer.Monga tafotokozera mu Zipangizo ndi Njira, kuwerengera kofanana (kuwongolera kwachiwiri ndi kwachitatu ndi kuwerengera zitsanzo) kunagwiritsidwa ntchito kuwerengera PFE mumdima wakuda wabuluu ndi wofiira mu Chithunzi 2, motsatira.Ponseponse, mtengo wapakati wa PFE wa zobwereza zitatuzi ndi 78% ± 2% pansalu ya juzi ndi 74% ± 2% pazida zomenyetsa thonje.
Kuti muwonetse momwe kachitidwe kachitidwe kachitidwe kachitidwe, masks ovomerezeka azachipatala a ASTM 2100 (L2, L3) ndi opumira a NIOSH (N95) adawunikidwanso.Muyezo wa ASTM F2100 umayika kusefera kwa tinthu tating'onoting'ono ta 0.1 µm tinthu tating'onoting'ono ta level 2 ndi masks a Level 3 kukhala ≥ 95% ndi ≥ 98%, motsatana.[5] Mofananamo, opumira a N95 ovomerezeka a N95 ayenera kusonyeza kusefa kwa ≥95% kwa atomu ya NaCl nanoparticles ndi mainchesi a 0.075 µm.[24] Rengasamy et al.Malinga ndi malipoti, masks ofanana a N95 amawonetsa mtengo wa PFE wa 99.84% -99.98%, [25] Zangmeister et al.Malinga ndi malipoti, N95 yawo imapanga kusefera kocheperako kuposa 99.9%, [14] pomwe Joo et al.Malinga ndi malipoti, masks a 3M N95 adatulutsa 99% ya PFE (300 nm particles), [16] ndi Hao et al.N95 PFE (300 nm particles) yomwe inanenedwa ndi 94.4%.[17] Kwa masks awiri a N95 omwe adatsutsidwa ndi Shakya et al.ndi mipira ya latex ya 0.1 µm, PFE idatsika pafupifupi pakati pa 80% ndi 100%.[19] Pamene Lu et al.Pogwiritsa ntchito mipira ya latex yofanana kukula kwake kuwunika masks a N95, pafupifupi PFE akuti ndi 93.8%.[20] Zotsatira zomwe zapezedwa pogwiritsa ntchito zida zomwe zafotokozedwa mu ntchitoyi zikuwonetsa kuti PFE ya chigoba cha N95 ndi 99.2 ± 0.1%, zomwe zimagwirizana bwino ndi maphunziro ambiri am'mbuyomu.
Masks opangira opaleshoni ayesedwanso m'maphunziro angapo.Masks opangira opaleshoni a Hao et al.adawonetsa PFE (300 nm particles) ya 73.4%, [17] pomwe masks atatu opangira opaleshoni adayesedwa ndi Drewnick et al.PFE yopangidwa kuchokera pafupifupi 60% mpaka pafupifupi 100%.[15] (Maski otsiriza angakhale chitsanzo chovomerezeka.) Komabe, Zangmeister et al.Malinga ndi malipoti, kusefera pang'ono kwa masks awiri opangira opaleshoni omwe adayesedwa ndikokwera pang'ono kuposa 30%, [14] kutsika kwambiri kuposa masks opangira opaleshoni omwe adayesedwa mu kafukufukuyu.Mofananamo, "chigoba cha opaleshoni ya buluu" choyesedwa ndi Joo et al.Tsimikizirani kuti PFE (300 nm particles) ndi 22% yokha.[16] Shakya et al.inanena kuti PFE ya masks opangira opaleshoni (pogwiritsa ntchito 0.1 µm latex particles) idatsika pafupifupi 60-80%.[19] Pogwiritsa ntchito mipira ya latex yofanana kukula kwake, chigoba cha opaleshoni cha Lu et al. chinatulutsa zotsatira za PFE za 80.2%.[20] Poyerekeza, PFE ya chigoba chathu cha L2 ndi 94.2 ± 0.6%, ndipo PFE ya L3 mask ndi 94.9 ± 0.3%.Ngakhale ma PFEwa amaposa ma PFE ambiri m'mabuku, tiyenera kuzindikira kuti palibe chiphaso chomwe chatchulidwa mu kafukufuku wam'mbuyomu, ndipo masks athu opangira opaleshoni apeza ziphaso za Level 2 ndi Level 3.
Momwemonso zida zopangira chigoba zomwe zili pachithunzi 2 zidawunikidwa, mayeso atatu adachitidwa pazida zina zisanu ndi chimodzi kuti zitsimikizire kukwanira kwake pachigoba ndikuwonetsa magwiridwe antchito a chipangizo cha PFE.Chithunzi 3 chimapanga miyeso ya PFE yazinthu zonse zoyesedwa ndikuziyerekeza ndi mfundo za PFE zomwe zimapezedwa powunika zida zovomerezeka za L3 ndi N95.Kuchokera pa masks 11 / zida zosankhidwa za osankhidwa kuti agwire ntchitoyi, magwiridwe antchito osiyanasiyana a PFE amatha kuwoneka bwino, kuyambira ≈10% mpaka kufupi ndi 100%, mogwirizana ndi maphunziro ena, [8, 9, 15] ndi zofotokozera zamakampani. Palibe ubale womveka bwino pakati pa PFE ndi PFE.Mwachitsanzo, zida zokhala ndi zofanana (ziwiri za thonje 100% ndi thonje muslin) zimawonetsa ma PFE osiyanasiyana (14%, 54%, ndi 13%, motsatana).Koma ndikofunikira kuti magwiridwe antchito otsika (mwachitsanzo, 100% thonje A; PFE ≈ 14%), magwiridwe antchito apakatikati (mwachitsanzo, 70%/30% thonje / polyester blend; PFE ≈ 49%) ndi magwiridwe antchito apamwamba (mwachitsanzo, Nsalu ya sweatshirt; PFE ≈ 78%) Nsaluyo imatha kudziwika bwino pogwiritsa ntchito zida za PFE zomwe zafotokozedwa mu ntchitoyi.Makamaka nsalu za majuzi ndi zida zomenyetsa thonje zidachita bwino kwambiri, ma PFE kuyambira 70% mpaka 80%.Zida zapamwamba zoterezi zimatha kudziwika ndikuwunikidwa mwatsatanetsatane kuti mumvetse makhalidwe omwe amachititsa kuti azisefera kwambiri.Komabe, tikufuna kukumbutsani kuti chifukwa zotsatira za PFE zazinthu zomwe zili ndi malongosoledwe amakampani ofanana (ie zida za thonje) ndizosiyana kwambiri, izi sizikuwonetsa kuti ndi zinthu ziti zomwe zili zothandiza kwambiri pamaski a nsalu, ndipo sitikufuna kutengera katunduyo- magulu azinthu.Mgwirizano wa ntchito.Timapereka zitsanzo zenizeni zowonetsera kusamalitsa, kuwonetsa kuti muyesowo umakwaniritsa zonse zomwe zingatheke kusefa, ndikupereka kukula kwa cholakwikacho.
Tinapeza zotsatirazi za PFE kuti titsimikizire kuti zida zathu zili ndi mphamvu zambiri zoyezera, zolakwika zochepa, komanso poyerekeza ndi zomwe zapezeka m'mabuku.Mwachitsanzo, Zangmeister et al.Zotsatira za PFE za nsalu zingapo zolukidwa za thonje (mwachitsanzo "Thonje 1-11″) (89 mpaka 812 ulusi pa inchi) zimanenedwa.Mu 9 mwa zida 11, "kusefera kocheperako" kumayambira 0% mpaka 25%;PFE yazinthu zina ziwirizi ndi pafupifupi 32%.[14] Mofananamo, Konda et al.Zambiri za PFE za nsalu ziwiri za thonje (80 ndi 600 TPI; 153 ndi 152 gm-2) zimanenedwa.PFE imachokera ku 7% mpaka 36% ndi 65% mpaka 85%, motero.Pakufufuza kwa Drewnick et al., mu nsalu za thonje zansanjika imodzi (ie thonje, thonje loluka, moleton; 139–265 TPI; 80–140 gm–2), mitundu yosiyanasiyana ya PFE imakhala pafupifupi 10% mpaka 30%.Pakufufuza kwa Joo et al., 100% ya thonje yawo ili ndi PFE ya 8% (300 nm particles).Bagheri et al.ntchito polystyrene latex particles wa 0.3 mpaka 0.5 µm.PFE ya zipangizo zisanu ndi chimodzi za thonje (120-200 TPI; 136-237 gm-2) inayesedwa, kuyambira 0% mpaka 20%.[18] Choncho, zambiri mwa zipangizozi zimagwirizana bwino ndi zotsatira za PFE za nsalu zathu zitatu za thonje (ie Veratex Muslin CT, Fabric Store Cottons A ndi B), ndipo mphamvu zawo zowonongeka ndi 13%, 14% ndipo motsatira.54%.Zotsatira izi zikuwonetsa kuti pali kusiyana kwakukulu pakati pa zinthu za thonje ndi kuti zinthu zomwe zimatsogolera ku PFE yapamwamba (ie Konda et al.'s 600 TPI thonje; thonje B wathu) sizimveka bwino.
Poyerekeza izi, timavomereza kuti ndizovuta kupeza zida zoyesedwa m'mabuku zomwe zili ndi mikhalidwe yofanana (ie, kapangidwe kazinthu, kuluka ndi kuluka, TPI, kulemera, ndi zina) ndi zida zomwe zayesedwa mu phunziroli, ndi Choncho sitingathe kuyerekezedwa mwachindunji.Kuonjezera apo, kusiyana kwa zida zomwe olemba amagwiritsira ntchito ndi kusowa kovomerezeka kumapangitsa kuti zikhale zovuta kufananitsa bwino.Komabe, zikuwonekeratu kuti kugwirizana kwa ntchito / kachitidwe ka nsalu wamba sikumveka bwino.Zidazi zidzayesedwanso ndi zida zokhazikika, zosinthika komanso zodalirika (monga zida zomwe zafotokozedwa mu ntchitoyi) kuti mudziwe maubwenzi awa.
Ngakhale pali zolakwika zowerengera (0-5%) pakati pa kubwereza kamodzi (0-4%) ndi zitsanzo zomwe zawunikidwa patatu, zida zomwe zaperekedwa mu ntchitoyi zidakhala chida chothandiza poyesa PFE yazinthu zosiyanasiyana.Nsalu wamba ku masks ovomerezeka azachipatala.Ndizofunikira kudziwa kuti pakati pa zida za 11 zoyesedwa pa Chithunzi 3, cholakwika chofalitsa σprop chimaposa kupatuka kokhazikika pakati pa miyeso ya PFE yachitsanzo chimodzi, ndiko kuti, σsd ya 9 mwa zida 11;kusiyanitsa ziwirizi kumachitika mumtengo Wapamwamba kwambiri wa PFE (ie L2 ndi L3 chigoba).Ngakhale zotsatira zoperekedwa ndi Rengasamy et al.Kuwonetsa kuti kusiyana pakati pa zitsanzo zobwerezabwereza ndizochepa (ie, kubwereza kasanu <0.29%), [25] adaphunzira zipangizo zodziwika bwino zosefera zomwe zimapangidwira makamaka kupanga chigoba: zinthuzo zikhoza kukhala zofanana, ndipo mayesero ndi awa. gawo la gulu la PFE litha kukhala lokhazikika.Ponseponse, zotsatira zomwe zapezedwa pogwiritsa ntchito zida zathu zimagwirizana ndi data ya PFE komanso milingo ya certification yomwe ofufuza ena amapeza.
Ngakhale PFE ndichizindikiro chofunikira choyezera momwe chigoba chimagwirira ntchito, pakadali pano tiyenera kukumbutsa owerenga kuti kusanthula kwathunthu kwa zinthu zamtsogolo za chigoba kuyenera kuganiziranso zinthu zina, ndiko kuti, kutulutsa kwazinthu (ndiko kuti, kudzera pakutsika kwapanikizi kapena kuyesedwa kosiyana. ).Pali malamulo mu ASTM F2100 ndi F3502.Kupuma kovomerezeka ndikofunikira kuti wovalayo atonthozedwe komanso kupewa kutuluka kwa m'mphepete mwa chigoba panthawi yopuma.Popeza kuti PFE ndi mpweya wazinthu zambiri zomwe zimagwiritsidwa ntchito nthawi zambiri zimakhala zofanana, kuyeza kwa kutsika kuyenera kuchitidwa limodzi ndi muyeso wa PFE kuti muwone bwino momwe chigobacho chimagwirira ntchito.
Tikukulimbikitsani kuti malangizo opangira zida za PFE molingana ndi ASTM F2299 ndi ofunikira pakuwongolera mosalekeza kwa miyezo, kupanga zidziwitso za kafukufuku zomwe zitha kufananizidwa pakati pa ma laboratories ofufuza, komanso kupititsa patsogolo kusefera kwa aerosol.Ingodalira muyezo wa NIOSH (kapena F3502), womwe umatchula chipangizo chimodzi (TSI 8130A) ndikuletsa ochita kafukufuku kugula zipangizo za turnkey (mwachitsanzo, machitidwe a TSI).Kudalira machitidwe okhazikika monga TSI 8130A ndikofunikira paziphaso zamakono, koma kumachepetsa chitukuko cha masks, zopumira, ndi matekinoloje ena osefera aerosol omwe amatsutsana ndi kupita patsogolo kwa kafukufuku.Ndizofunikira kudziwa kuti muyezo wa NIOSH unapangidwa ngati njira yoyesera zopumira pansi pazovuta zomwe zimayembekezereka zida izi zikafunika, koma mosiyana, masks opangira opaleshoni amayesedwa ndi njira za ASTM F2100/F2299 .Maonekedwe ndi mawonekedwe a masks ammudzi ali ngati masks opangira opaleshoni, zomwe sizitanthauza kuti ali ndi ntchito yabwino kwambiri yosefera ngati N95.Ngati masks opangira opaleshoni amawunikiridwabe molingana ndi ASTM F2100/F2299, nsalu wamba ziyenera kuyesedwa pogwiritsa ntchito njira pafupi ndi ASTM F2100/F2299.Kuphatikiza apo, ASTM F2299 imalola kusinthasintha kowonjezera mu magawo osiyanasiyana (monga kuthamanga kwa mpweya komanso kuthamanga kwapamwamba pamaphunziro a kusefera koyenera), zomwe zitha kupangitsa kuti ikhale mulingo wapamwamba kwambiri pamalo ofufuzira.
Nthawi yotumiza: Aug-30-2021