Facing shortages of personal protective equipment, some clinicians have advocated the use of barrier enclosures (typically mounted over the head, with and without suction) to contain aerosol emissions from coronavirus disease 2019 (COVID-19) patients. There is, however, little evidence for its usefulness. To test the effectiveness of such a device, we built a manikin that can expire micron-sized aerosols at flow rates close to physiological conditions. We then placed the manikin inside the enclosure and used a laser sheet to visualize the aerosol leaking out. We show that with sufficient suction, it is possible to effectively contain aerosol from the manikin, reducing aerosol exposure outside the enclosure by 99%. In contrast, a passive barrier without suction only reduces aerosol exposure by 60%.

中文翻译：

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有效设计屏障外壳以遏制 COVID-19 患者的气溶胶排放

面对个人防护设备的短缺，一些临床医生提倡使用屏障罩（通常安装在头上，有或没有吸力）来控制 2019 年冠状病毒病 (COVID-19) 患者的气溶胶排放。然而，几乎没有证据证明它的有用性。为了测试这种设备的有效性，我们构建了一个人体模型，可以在接近生理条件的流速下释放微米级气溶胶。然后，我们将人体模型放置在外壳内，并使用激光片观察泄漏的气溶胶。我们表明，通过足够的吸力，可以有效地控制人体模型中的气溶胶，从而将气溶胶暴露在外壳外减少 99%。相比之下，没有吸力的被动屏障只能将气溶胶暴露减少 60%。