這篇論文（https://doi.org/10.1017/dmp.2020.35）是我Fit Test*視頻中試驗(yàn)方法的來(lái)源，它提供了一個(gè)簡(jiǎn)單、便宜、易操作的定性適合性試驗(yàn)（QLFT）方法，讓更多的人評(píng)估自己佩戴的口罩/呼吸器是否密合成為了可能。但如論文中所說(shuō)，這是一個(gè)很初級(jí)的研究，方法的安全性需要進(jìn)一步評(píng)估。但對(duì)一些人來(lái)說(shuō)，未經(jīng)安全性認(rèn)證但行之有效的QLFT方法帶來(lái)的風(fēng)險(xiǎn)，跟不確定自己用的呼吸器能否密合帶來(lái)的風(fēng)險(xiǎn)相比，前者或許會(huì)小得多。

*有適合性試驗(yàn)、適合性檢驗(yàn)、密合度測(cè)試之類的譯法

請(qǐng)注意：論文中的試驗(yàn)方法存在風(fēng)險(xiǎn)，請(qǐng)讀者仔細(xì)閱讀論文中的“討論”及其他部分標(biāo)紅的風(fēng)險(xiǎn)提示語(yǔ)，并謹(jǐn)慎使用試驗(yàn)方法，自擔(dān)風(fēng)險(xiǎn)。

論文中提到的傳統(tǒng)QLFT套件都可以在BV1Gj411f7Tt中看到。

由于譯者水平有限，部分翻譯可能存在不準(zhǔn)確、不到位的情況。個(gè)別地方譯者不知道怎么翻，有擺爛行為，請(qǐng)讀者諒解，歡迎在評(píng)論區(qū)補(bǔ)充合適的翻譯。術(shù)語(yǔ)第一次出現(xiàn)時(shí)會(huì)用方括號(hào)寫出縮寫，再次出現(xiàn)會(huì)直接使用縮寫。

以下是全文搬運(yùn)+正文翻譯，星號(hào)（*）是譯者添加的備注，論文原文中的括號(hào)在譯文中仍使用圓括號(hào)，譯者補(bǔ)充的括號(hào)為方括號(hào)。由于專欄不能添加上標(biāo)，論文中表示引用的數(shù)字均用小一號(hào)的字體展現(xiàn)。譯文約4300字，大約需要11-14分鐘閱讀。

在家和在工作地點(diǎn)也能做的適合性試驗(yàn)——不需要專業(yè)套件的定性測(cè)試

Performing Qualitative Mask Fit Testing Without a Commercial Kit: Fit Testing Which Can Be Performed at Home and at Work

作者團(tuán)隊(duì)：Eugenia O’Kelly, BA ; Anmol Arora ; Charlotte Pearson; James R. Ward, PhD ; P. John Clarkson, ScD

摘要

目的：定性的適合性試驗(yàn)[QLFT]是一種確認(rèn)面罩適合性[fit]的手段，常用于如N95和FFP3這類緊貼面部的面罩。由于冠病-19造成對(duì)測(cè)試設(shè)備的需求增加，進(jìn)一步引起了設(shè)備短缺，許多機(jī)構(gòu)不得不放棄適合性試驗(yàn)。QLFT需要用到三種關(guān)鍵材料：測(cè)試溶液、噴霧器[nebulizer]和測(cè)試頭罩。由于已經(jīng)有了對(duì)測(cè)試溶液替代品的研究，本研究將評(píng)估噴霧器和頭罩的替代方案。

方法：我們?yōu)閷I(yè)套件中的噴霧器選用了四種替代方案，為頭罩選了兩種方案。三名研究人員佩戴不同口罩評(píng)估替代品的實(shí)用性和準(zhǔn)確性，以選出最可行的方案。

結(jié)果：香薰機(jī)和較小的頭罩具有較高的靈敏度和準(zhǔn)確性。

結(jié)論：香薰機(jī)在QLFT中具有迅速、簡(jiǎn)便、便宜的顯著優(yōu)勢(shì)。我們的研究指出，在無(wú)法獲取傳統(tǒng)的測(cè)試套件時(shí)，香薰機(jī)和自制頭罩是很好的替代品，但它們的安全性和可靠性還需要后續(xù)的實(shí)驗(yàn)來(lái)評(píng)估。

關(guān)鍵詞：behavioral risk factor surveillance, safety management, health communication, quality of health care, risk assessment

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ABSTRACT

Objective: Qualitative fit testing is a popular method of ensuring the fit of sealing face masks such as N95 and FFP3 masks. Increased demand due to the coronavirus disease 2019 (COVID-19) pandemic has led to shortages in testing equipment and has forced many institutions to abandon fit testing. Three key materials are required for qualitative fit testing: the test solution, nebulizer, and testing hood. Accessible alternatives to the testing solution have been studied. This exploratory qualitative study evaluates alternatives to the nebulizer and hoods for performing qualitative fit testing.

Methods: Four devices were trialed to replace the test kit nebulizer. Two enclosures were tested for their ability to replace the test hood. Three researchers evaluated promising replacements under multiple mask fit conditions to assess functionality and accuracy.

Results: The aroma diffuser and smaller enclosures allowed participants to perform qualitative fit tests quickly and with high accuracy.

Conclusions: Aroma diffusers show significant promise in their ability to allow individuals to quickly, easily, and inexpensively perform qualitative fit testing. Our findings indicate that aroma diffusers and homemade testing hoods may allow for qualitative fit testing when conventional apparatus is unavailable. Additional research is needed to evaluate the safety and reliability of these devices.

Key Words: behavioral risk factor surveillance, safety management, health communication, quality of health care, risk assessment

QLFT可以用來(lái)評(píng)估諸如N95和FFP3這類緊貼面部的口罩的適合性，但不幸的是，在冠病-19大流行期間，對(duì)個(gè)人防護(hù)設(shè)備及適合性試驗(yàn)[FT]設(shè)備需求的劇增，以及需求劇增后供應(yīng)的不足，迫使許多機(jī)構(gòu)放棄了FT1。

Qualitative fit testing provides the ability to ensure acceptable fit of a sealing face mask such as an N95 or FFP3. Unfortunately, during the coronavirus disease 2019 (COVID-19) pandemic, a dramatic increase in the demand and use of protective equipment and fit testing equipment, coupled with severe supply shortages, has forced many institutions to abandon fit testing.1

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適合性是一個(gè)重要指標(biāo)，它決定了口罩能不能阻止細(xì)顆粒物的呼出和吸入。此前的研究提到，即便口罩材料本身有高過濾效率，如果不能密合，那么口罩的防護(hù)能力也會(huì)大打折扣。Huff等人的研究中通過使用霧化后的放射性元素锝，發(fā)現(xiàn)佩戴呼吸器時(shí)不能有效密合是導(dǎo)致沾染的主要原因2。這個(gè)發(fā)現(xiàn)被Cooper等人的研究結(jié)果所支持。Cooper團(tuán)隊(duì)在研究中發(fā)現(xiàn)，從外科口罩邊緣泄露的氣流量是總氣流量的三分之一；對(duì)于緊貼面部的呼吸器來(lái)說(shuō)，泄露量是總氣流量的六分之一3。

Fit is a primary factor in determining whether a mask is capable of reducing the spread and inhalation of fine particles. Previous studies have noted that, even if the materials of a mask have high filtration efficiency, the effectiveness of the mask is hampered by an imperfect seal. A study by Huff et al., using nebulized radioactive technetium, found that an ineffective seal is the principal cause of airborne contamination among those wearing respirators.2 This finding is supported by the findings of Cooper et al., who found that leakage around masks accounted for one-third of the airflow across the mask for surgical masks and one-sixth of the flow for respirators.3

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QLFT為半面罩（如N95、FFP3*）測(cè)試適合性的情況最多見，因?yàn)樗啾绕鸲康倪m合性試驗(yàn)[QNFT]來(lái)說(shuō)，更便宜、[設(shè)備和材料]更易得、更快，也占用更少的人員時(shí)間[staff time]4。正因如此，在醫(yī)院這種高吞吐率對(duì)設(shè)施性能[facility performance]至關(guān)重要的機(jī)構(gòu)**，QLFT得到了廣泛應(yīng)用5。

[*譯者：這里原文是FPP3，顯然是手誤，應(yīng)為FFP3。]

[**譯者水平有限，這里怎么翻都別扭]

Qualitative testing is most commonly adopted to assess the fit of half-face respirators such as N95 and FPP3 masks4 as it is less expensive, more accessible, faster, and less demanding of staff time than the alternative of quantitative fit testing.4 Qualitative testing is widely used in hospitals, where a high throughput rate is critical for facility performance.5

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在正常情況下，QLFT需要的設(shè)備既不貴，又不難獲得。QLFT通常需要三件道具：一個(gè)測(cè)試用的頭罩、一種測(cè)試溶液霧化器，以及用于霧化的溶液。不幸的是，斷裂的供應(yīng)鏈和激增的需求使得這些設(shè)備一套難求。在美國(guó)，購(gòu)買這些設(shè)備的人要面臨缺貨的問題，或至少等待8周[才能拿到貨]。

Under normal circumstances, the equipment required for qualitative fit testing is affordable and accessible. The tests usually require 3 items: a wearable testing hood; a testing solution aerosolizer; and an aerosolized test solution. Unfortunately, disruption to supply chains and a surge in demand has limited their availability. Those seeking to purchase such equipment currently face out of stock notices or wait times, in the United States, of up to and over 8 wk.

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為了醫(yī)院和其他行業(yè)能為他們的員工提供應(yīng)有的保護(hù)，解決FT設(shè)備供應(yīng)危機(jī)變得至關(guān)重要。此前的研究已經(jīng)展示了自制FT溶液的可行性6,7，本研究就作為一個(gè)初始的、探索性質(zhì)的研究，評(píng)估QLFT中頭罩和霧化器的替代品的有效性。

Solving the fit testing supply crisis is critical to enable hospitals and businesses to properly protect their workers. Prior studies have already shown the feasibility of making a homemade fit testing solution.6,7 This initial exploratory study aims to assess the effectiveness of alternatives to the mechanical elements of the qualitative fit test: the fit testing hood and nebulizer.

方法

測(cè)試與驗(yàn)證

三位測(cè)試人員在進(jìn)行QLFT前先接受了QNFT，來(lái)評(píng)估他們佩戴的口罩的適合性。相比起QLFT，計(jì)算口罩內(nèi)外顆粒物數(shù)量的比值的QNFT準(zhǔn)確性更佳，是一種非常準(zhǔn)確的衡量呼吸器適合性的方法6,8。QNFT的結(jié)果將用來(lái)判斷QLFT的結(jié)果（有味道vs無(wú)味道）是否準(zhǔn)確。我們將使用Portacount 8038+——一套能測(cè)試N95口罩的設(shè)備，依照OSHA protocol 29CFR1910.134來(lái)執(zhí)行QNFT。團(tuán)隊(duì)中的一位成員先接受測(cè)試，其他人隨后接受相同的測(cè)試，以確認(rèn)設(shè)備確實(shí)有效*。更多信息可以在線上的補(bǔ)充數(shù)據(jù)里獲取。

[*譯者：這里應(yīng)該說(shuō)的是QLFT的設(shè)備]

METHODS

Testing and Verification

Three testers underwent quantitative fit tests to assess the fit of the masks on their face before assessing qualitative fit methods. Quantitative fit testing, which measures the number of particles inside and outside of a face mask, is a highly accurate means of measuring fit and is more accurate than qualitative fit testing.6,8 Results from the quantitative fit tests were used to determine what sensation (taste vs no taste) would be considered the correct response in the qualitative fit testing. Quantitative fit tests were conducted with a Portacount 8038+ using OSHA protocol 29CFR1910.134 and the settings that allow the testing of N95 masks. One member of the team performed initial testing. Additional testers were brought in to confirm and assess promising devices. More information can be found in the online Supplemental Data.

測(cè)試溶液

Fakherpour團(tuán)隊(duì)和Mitchell團(tuán)隊(duì)已經(jīng)找到了既有效又能在家中簡(jiǎn)單制作的糖精鈉溶液配方6,9，在本研究中使用的配方正是基于他們的研究結(jié)果。正式測(cè)試溶液由830毫克糖精鈉和100毫升蒸餾水混合而成；靈敏度測(cè)試溶液由415毫克糖精鈉和100毫升蒸餾水混合而成，該溶液的濃度在Fakherpour和Mitchel兩個(gè)團(tuán)隊(duì)使用的閾值濃度之間。

Testing Solution

Fakherpour et al. and Mitchell et al. have developed effective sodium saccharin testing formulas which can easily be made at home.6,9 Our formula was based on these studies. The testing solution consists of 830-mg sodium saccharin to 100-mL distilled water. Our sensitivity/threshold solution contained a sodium saccharin concentration between the threshold solution of Fakherpour et al. and Mitchel et al., using 415-mg sodium saccharin per 100 mL. A commercial fit test nebulizer was used to ensure each test subject could detect

the saccharin solution.

設(shè)備

我們測(cè)試了四種用來(lái)代替原版燈泡狀霧化器的設(shè)備，它們分別是：超聲波霧化器（品牌AGPTEK，總部在中國(guó)廣東）、小噴瓶、迷你棍狀加濕器（品牌JISULIFE，總部在中國(guó)廣東）和一個(gè)香薰機(jī)（品牌VicTsing，總部在加州的森尼維爾）。小噴瓶和迷你加濕器的噴霧量并不可知，JISULIFE的迷你加濕器外包裝上聲稱噴霧量在25-40毫升每小時(shí)*。AGPTEK的超聲波霧化器聲稱噴霧量至少是400毫升每小時(shí)。

[*譯者：看起來(lái)前后文沖突對(duì)吧？原文如此，我也不知道怎么回事。]

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三種設(shè)備持續(xù)運(yùn)行60秒，而小噴瓶則朝著頭罩里噴10次。如果在這期間沒有嘗出味道，那么測(cè)試結(jié)果記為“無(wú)味道”。

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Devices

Four devices were tested for their ability to replace the bulb nebulizer used for qualitative test kits. These included an ultrasonic mist maker (from AGPTEK, headquarters Guangdong, China), a spray bottle, a miniature wand humidifier (from JISULIFE, headquarters Guangdong, China), and an essential oil diffuser (from VicTsing, headquarters Sunnyvale, CA). Flow rate information was not available for the spray bottle or miniature humidifier. The mini humidifier by JISULIFE packaging stated a diffusion rate of 25-40 mL/h. The ultrasonic mist maker by AGPTEK claims to produce at least 400 mL/h.

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Devices were run for 60s, or in the case of the spray bottle, for up to 10 sprays. If no taste could be detected within that period, the test condition was judged as “no taste”.

試驗(yàn)用Enclosures

在QLFT中，傳統(tǒng)的enclosure是一個(gè)頭罩，帶有一個(gè)可供擠壓式霧化器伸進(jìn)去產(chǎn)生霧氣的圓形小洞（小洞同時(shí)也有通風(fēng)的作用）。跟其他的設(shè)備一樣，這頭罩挺貴，并且在大流行期間也很難買到。我們測(cè)試了兩種替代品：一個(gè)邊長(zhǎng)11.81英寸[譯者：約30厘米]的透明[clear]方形儲(chǔ)物盒，以及一個(gè)結(jié)實(shí)的、容積2加侖[譯者：約10升]的塑料袋。我們同時(shí)也測(cè)試了傳統(tǒng)的FT頭罩。傳統(tǒng)頭罩上的小洞是為水平出霧的霧化器設(shè)計(jì)的，因此我們把一根PVC彎管接到小洞上，讓垂直出霧的設(shè)備產(chǎn)生的霧氣能順利進(jìn)入頭罩里。

Testing Enclosures

In qualitative testing, a hood with a small circular opening for ventilation and insertion of the squeeze nebulizer is used to concentrate the testing mist. Like the rest of the testing equipment, these hoods are expensive and, under these pandemic conditions, difficult to obtain. We tested 2 alternative testing enclosures to replace the hood: a clear storage cube measuring 11.81 inches square and a sturdy 2-gallon plastic bag. We also tested the devices with a commercial fit test hood. When testing the hood, which is designed for a horizontally discharging aerosolizing device, we used a piece of curved PVC fit to the hole in the testing hood to help direct the mist from the vertically discharging devices.

口罩

測(cè)試中使用了兩種口罩，一種是3M的N95，一種是中國(guó)制造商生產(chǎn)的KN95。

Mask

Two different masks were worn during testing, an N95 mask manufactured by 3M and a KN95 mask from a Chinese manufacturer.

為了評(píng)估霧化設(shè)備和頭罩的性能并準(zhǔn)確預(yù)測(cè)適合性的問題，我們?cè)O(shè)計(jì)了幾種不同的適合性狀態(tài)，進(jìn)行了五次測(cè)試，測(cè)試使用的口罩是未加改動(dòng)的N95和KN95。測(cè)試人員會(huì)佩戴N95進(jìn)行三次額外的測(cè)試，這三次測(cè)試中，佩戴者的面部和N95之間會(huì)故意留出縫隙。第一次[額外]測(cè)試中，測(cè)試人員會(huì)把手指伸到眼睛下方的皮膚與口罩之間，在鼻子附近制造一個(gè)空隙；第二次[額外]測(cè)試中，他們會(huì)把手指伸到下巴與口罩之間，制造一個(gè)空隙；終極最后一次[額外]測(cè)試中，他們會(huì)在臉頰和口罩側(cè)面之間用手指制造一個(gè)空隙。這三個(gè)測(cè)試能讓我們知道，我們用的測(cè)試設(shè)備檢測(cè)適合性問題的能力究竟有多強(qiáng)。

To assess the ability of the device and enclosure to accurately predict fit issues, 5 tests were conducted in different fit states. Tests were performed with the unmodified N95 and KN95.

The wearer then performed 3 additional tests with the N95 while intentionally causing a fit gap. For 1 test, they placed the tip of their finger between the mask and the skin beneath

their eye, causing a gap in the nose area. For the other test, they placed the tip of their finger between the bottom of the mask and their chin area, causing a chin gap. Finally, they placed the tip of their finger between the cheeks and edge of the mask. These 3 tests enabled us to assess how well the testing setup could detect specific fit issues.

結(jié)果

霧化設(shè)備

四種設(shè)備中的三種都能讓測(cè)試人員嘗到靈敏度測(cè)試溶液的味道（見圖一）。棍狀加濕器不好用，沒能讓測(cè)試人員嘗到明顯的味道；霧化器和噴瓶能讓測(cè)試人員嘗到味道，但會(huì)有糟糕的副作用，比如讓口罩變濕；香薰機(jī)能產(chǎn)生準(zhǔn)確的結(jié)果，其準(zhǔn)確性與商用的QLFT設(shè)備一致6。

RESULTS

Aerosolization Devices

The testers were able to taste the sensitivity solution with 3 of the devices used (see Figure 1). The wand humidifier proved difficult to use and did not produce a clear taste sensation. The mist maker and spray bottle produced a taste sensation but had undesirable side effects such as causing the mask to become wet. The aroma diffuser produced accurate responses. The accuracy using this aroma diffuser was in line with the reported accuracy of commercial qualitative fit testing kits.6

頭罩

小一點(diǎn)的頭罩在和某些設(shè)備（不是所有設(shè)備）搭配時(shí)能有更迅速的結(jié)果。噴瓶在傳統(tǒng)頭罩里表現(xiàn)不佳，在10升塑料袋里則完全沒法用。

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在同香薰機(jī)和超聲波霧化器搭配時(shí)，頭罩小一點(diǎn)，準(zhǔn)確性會(huì)更高，出結(jié)果的速度也更快。最小的頭罩——塑料袋，在試驗(yàn)中出現(xiàn)不準(zhǔn)確結(jié)果的次數(shù)最少，得出正確結(jié)果的速度最快；更大的頭罩會(huì)有更低的準(zhǔn)確性，也需要更長(zhǎng)的測(cè)試時(shí)間才能出結(jié)果。

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Testing Enclosures

Smaller testing enclosures allowed for faster detection of the testing solution in some, but not all, devices. The spray bottle did not function well in the hood and was unable to fit into the 2-gallon bag.

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The smaller testing enclosures benefited both the accuracy and the detection speed when using the aroma diffuser and ultrasonic mist maker. The smallest enclosure, the plastic bag, produced the fewest inaccurate results and allowed for correct detection in the shortest period of time. Larger testing enclosures incurred greater inaccuracy and longer times to detection.

討論

總結(jié)一下重要發(fā)現(xiàn)

我們的結(jié)果顯示，便宜的自制溶液和家用設(shè)備可以有效地執(zhí)行QLFT，并且這套容易重復(fù)的試驗(yàn)，能讓面罩佩戴者在家或在工作地點(diǎn)就能簡(jiǎn)單、快速地檢查面罩的適合性狀態(tài)（見圖2）。我們發(fā)現(xiàn)香薰機(jī)和帶拉鏈的儲(chǔ)物袋分別是傳統(tǒng)霧化器和頭罩的最佳替代品，能產(chǎn)出最準(zhǔn)確的結(jié)果，它們的準(zhǔn)確程度、可靠性和易用性都超出了我們的預(yù)期。在無(wú)法獲得/買不起傳統(tǒng)QLFT套件的時(shí)候，它們是挺有用的替代品。不過必須強(qiáng)調(diào)的一點(diǎn)是，我們的這項(xiàng)研究還很初級(jí)，使用的方法并沒有依照美國(guó)國(guó)家職業(yè)安全衛(wèi)生研究所（NIOSH）的規(guī)定，我們不能確定這個(gè)QLFT方法同使用商業(yè)套件的、標(biāo)準(zhǔn)的NIOSH方法相比，是不是同樣有效、同樣安全。將其他設(shè)備改造并用于QLFT可能會(huì)對(duì)使用者帶來(lái)風(fēng)險(xiǎn)，我們建議謹(jǐn)慎使用這套方法，使用者自負(fù)風(fēng)險(xiǎn)，我們概不負(fù)責(zé)。

DISCUSSION

Summary of Key Findings

Our results indicate that qualitative fit testing can be conducted effectively using inexpensive homemade testing solutions and household testing devices. Moreover, a simple, quick, and easily replicated at-home or work setup may enable users to test for proper fit of sealing face masks (see Figure 2). We found that aroma diffusers and zipper storage bags were the most accurate alternatives to typical solution nebulizers and testing hoods, respectively. The degree of success, reliability, and ease of set up for our homemade testing apparatus exceeded our expectations and suggests that alternative testing enclosures and nebulizers may prove useful where conventional apparatus is unavailable or unaffordable. However, it must be emphasized that this research is preliminary. The method proposed is not National Institute for Occupational Safety and Health (NIOSH) compliant. We cannot be sure if this method of qualitative testing is as effective or safe as standard NIOSH testing methods using commercially available equipment. Repurposing equipment for qualitative fit testing may come with risks to the wearer. We advise anyone who intends to use this method to proceed with caution and at their own risk.

表現(xiàn)不佳的設(shè)備和頭罩

我們不建議在FT中使用噴瓶和超聲波霧化器，它們會(huì)讓口罩肉眼可見地變濕，影響口罩的后續(xù)使用。

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我們的結(jié)果顯示，加濕器不適合用來(lái)做定性測(cè)試*。原因可能是我們測(cè)試棍狀加濕器的出霧量太小，也許出霧量更大的加濕器會(huì)更合適；當(dāng)然也可能是大多數(shù)加濕器內(nèi)部都含有的過濾元件將溶液里的糖精鈉過濾到了人能嘗出來(lái)的閾值之下，所以它不能用于FT。香薰機(jī)在沒有頭罩的情況下就已經(jīng)良好了，與小頭罩搭配時(shí)表現(xiàn)還有提升。在不用頭罩進(jìn)行測(cè)試時(shí)，讓香薰機(jī)的霧氣與口罩接觸能提升測(cè)試的準(zhǔn)確性。如果用方形儲(chǔ)物盒做頭罩，跟無(wú)頭罩相比，提升并不大，因?yàn)樗冗^于大，又過于通風(fēng)，使得霧化的糖精鈉溶液沒法在口罩附近有足夠的濃度。一個(gè)更小的、更不透風(fēng)的盒子也許會(huì)更有效。

[*譯者：原文寫的是quantitative定量的，顯然是錯(cuò)誤，應(yīng)為qualitative定性的。]

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Poorly Functioning Devices and Enclosures

We do not recommend the use of the spray bottle or the ultrasonic mist maker for fit testing as both made the mask visibly wet and consequently compromised the future use of the mask.

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Our results indicate that humidifiers may not be fit for quantitative testing. While it is possible that the wand humidifier we tested provided an insufficient flow rate and that a more powerful humidifier might be adequate, it is likely that filters included with most humidifiers removed enough of the sodium saccharin to prevent the device from working as a fit testing device. The aroma diffuser was effective at testing masks without an enclosure but improved with a smaller space. Passing the aroma diffuser around the face so that the fog comes in contact with the mask improves the accuracy when no enclosure is used. The box we used provided little benefit over no enclosure. It was not small enough nor airtight enough to create a concentration of aerosolized sodium saccharin around the mask area. A smaller or more airtight box might be more effective.

表現(xiàn)出色的設(shè)備和頭罩

市面上能買到的香薰機(jī)能非常有效地霧化測(cè)試溶液。

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小頭罩，或者那些跟傳統(tǒng)頭罩尺寸相近的頭罩，跟香薰機(jī)配合時(shí)能最快得出最準(zhǔn)確的結(jié)果。

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如果沒有傳統(tǒng)頭罩，我們推薦使用容積至少為2加侖、魯棒的結(jié)實(shí)的freezer拉鏈儲(chǔ)物袋。一個(gè)大的freezer塑料袋，簡(jiǎn)單扣在頭上，保持袋口敞開，就是一個(gè)便宜好用的頭罩了。由于潛在的窒息風(fēng)險(xiǎn)，將塑料袋用于QLFT的時(shí)候要格外小心。這類頭罩只能用于知曉風(fēng)險(xiǎn)并能隨時(shí)取下塑料袋的成人。只有重結(jié)構(gòu)的塑料袋——比如Ziplock freezer塑料袋（品牌SC Johnson，總部在威斯康辛州的拉辛）才能用于FT，因?yàn)檫@些塑料袋比較硬的結(jié)構(gòu)和較重的塑料拉鏈能避免走形后堵住口鼻處的氣流。塑料袋在脖頸處絕對(duì)不能封上，應(yīng)保持敞開以供氣體交換。[拉鏈塑料袋的]重量和結(jié)構(gòu)也能避免和測(cè)試的設(shè)備纏繞在一起或在受試者脖頸附近封閉。輕、幾乎無(wú)結(jié)構(gòu)的塑料袋——比如保鮮袋和購(gòu)物塑料袋及任何產(chǎn)品的外包裝袋，會(huì)有更大的窒息風(fēng)險(xiǎn)，在任何情況下都絕對(duì)不能用于FT。塑料袋在任何時(shí)候都應(yīng)與佩戴者的口罩保持2英寸（約5厘米）的距離。為了保證測(cè)試者的安全，[進(jìn)行QLFT時(shí)]應(yīng)有另一名知曉風(fēng)險(xiǎn)的成人在場(chǎng)，這名成人要能隨時(shí)取下測(cè)試者頭上的塑料袋，以防任何可能的意外發(fā)生。在QLFT中使用任何未經(jīng)認(rèn)證的頭罩可能會(huì)帶來(lái)危險(xiǎn)，使用者后果自負(fù)。

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Successful Devices and Enclosures

Commercial aroma diffusers proved highly effective in aerosolizing the testing solution.

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Small enclosures, or those most similar to the conventional testing hood, produced the fastest and most accurate results when using an aroma diffuser.

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If a testing hood is not available, we recommend using a robust freezer zipper storage bag with at least a 2-gallon capacity. A large freezer plastic bag, kept open and placed over the head, proved an inexpensive and highly effective option. Due to the possible risk of suffocation, it is vital that extra caution is taken while using a plastic bag in this manner. This type of enclosure should only be used by risk-aware adults who are able to quickly and safely maneuver the bag on and off. Only plastic bags with heavier structure, such as Ziplock freezer bags (from SC Johnson, headquarters in Racine, WI), should be used. Their more rigid form and heavy plastic zipper resists deforming and blocking the air flow, nose, or mouth. Bags should never be sealed around the neck. The entirety of the bottom of the bag should be left open to promote airflow. The weight and structure also help prevent the bag from becoming tangled with the testing equipment or closing around the tester’s neck. Light, poorly structured bags, such as plastic takeout or grocery bags, garbage bags, or product packaging bags should never, under any circumstances, be used as these bags have a higher chance of causing suffocation. Bags should always be large enough to provide at least 2 inches in front of the mask when worn. For safety, a second adult should be present and aware at all times the bag is worn and able to quickly remove the bag in case of any issue. Testing with any enclosure not approved for qualitative fit testing may be hazardous and is undertaken at the risk of the user.

結(jié)論

盡管QLFT跟QNFT比起來(lái)準(zhǔn)確性更差，但它仍是評(píng)估面罩的適合性并確認(rèn)佩戴者得到保護(hù)的重要工具。人們可以用便宜的FT方案，讓他們能像其他人[指有專業(yè)套件的人]一樣保護(hù)自己，這比以往任何時(shí)候都重要。

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我們這項(xiàng)初始的研究說(shuō)明，用香薰機(jī)來(lái)代替昂貴的專業(yè)霧化器有一定可行性。在我們的測(cè)試中，香薰機(jī)的準(zhǔn)確性與專業(yè)套件的準(zhǔn)確性一致，甚至前者有時(shí)還更高。新的QLFT方法看起來(lái)前景不錯(cuò)，但需要進(jìn)一步的研究來(lái)確認(rèn)它的有效性和安全性。鑒于新冠病毒在全世界引起的持續(xù)增長(zhǎng)的風(fēng)險(xiǎn)，部分人可能會(huì)認(rèn)為未經(jīng)認(rèn)證的FT方法帶來(lái)的風(fēng)險(xiǎn)，要比戴著不密合、無(wú)法提供保護(hù)的呼吸器的風(fēng)險(xiǎn)小得多。不過，雖然本研究里展現(xiàn)的方法似乎表現(xiàn)不錯(cuò)，但不能認(rèn)為這個(gè)方法能夠替代傳統(tǒng)的QLFT方法，也絕對(duì)不能用在高危環(huán)境下（如health-care facilities*）。這個(gè)替代方法的安全性，以及使用包括苦味劑在內(nèi)的其他測(cè)試溶液的有效性，甚至使用苦味劑的替代溶液（比如aloe vera[譯者：蘆薈汁？]）的有效性，需要進(jìn)一步的研究10。

[*譯者：中文里好像沒有對(duì)應(yīng)的詞？這個(gè)詞通常包括醫(yī)院、診所、護(hù)理院、生殖中心這類地方，叫“衛(wèi)生保健機(jī)構(gòu)”？]

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CONCLUSIONS

Despite being less accurate than quantitative fit testing, qualitative testing remains a vital tool to ensure mask-wearers are protected by assessing mask fit. It is currently more important than ever that people have access to inexpensive fit testing protocols so that they can protect themselves as well as others.

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Our initial tests indicate that replacing the expensive test kit nebulizer with an aroma diffuser may be feasible. The accuracy of our tests were in line with, and often exceeded, the accuracy of qualitative fit tests performed with commercial solutions and equipment.6 This new qualitative testing method shows promise but requires additional research to ensure its effectiveness and safety. Given the growing risk the SARS-CoV-2 poses around the world, some may judge the potential risk of using this unproven testing method less severe than the risk of wearing a respirator whose poor fit does not protect the wearer. However, although the results presented in this study appear promising, the methods should not be interpreted as being a substitutable for conventional certified testing procedures and they must not be used in high-risk environments, such as health-care facilities. Future work is needed to assess the safety and efficacy of using alternative methods, as well as their ability to function with other testing solutions including bitter solutions and alterative testing solutions, such as aloe vera.10

關(guān)于作者（不翻）

About the Authors

Department of Engineering, Engineering Design Centre, Cambridge University, United Kingdom (Ms O’Kelly, Dr Ward, Prof Clarkson); Department of Medicine, Cambridge University, United Kingdom (Mr Arora) and Charles H Lundquist College of Business, University of Oregon, Eugene, Oregon (Ms Pearson).

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Correspondence and reprint requests to Eugenia O’Kelly, 999 Green Street, Apt 1505, San Francisco, CA USA 94133 (e-mail: eo339@cam.ac.uk).

致謝（不翻）

Acknowledgments

We give special thanks to Dr Ming Jeffrey Kao, who introduced us to the problem that motivated this study. We also thank Corinne O’Kelly for making this research possible.

補(bǔ)充材料

本論文的補(bǔ)充材料見https://doi.org/10.1017/dmp.2020.352

Supplementary Material

To view supplementary material for this article, please visit?https://doi.org/10.1017/dmp.2020.352

參考文獻(xiàn)

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https://doi.org/10.1017/dmp.2020.35

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