Suffield Research Centre, Chemical Biological Assessment and Protection Section, Defence Research and Development Canada, Medicine Hat, Alberta, Canada.
J Occup Environ Hyg. 2020 Nov-Dec;17(11-12):546-559. doi: 10.1080/15459624.2020.1829633. Epub 2020 Nov 9.
Most respirators employed in health care settings, and often in first responder and industrial settings, are intended for single-use: the user dons the respirator, performs a work activity, and then doffs and discards the respirator. However, in the current COVID-19 pandemic, in the presence of persistent shortages of personal protective equipment, extended use and reuse of filtering facepiece respirators are routinely contemplated by many health care organizations. Further, there is considerable current effort to understand the effect of sterilization on the possibility of reuse, and some investigations of performance have been conducted. While the ability of such a respirator to continue to provide effective protection after repeated sanitization cycles is a critical component of implementing its reuse, of equal importance is an understanding of the impact that reusing the respirator multiple times in a day while performing work tasks, and even extending its wear over multiple days, has on the workplace protective performance. In this study, we subjected a stockpiled quantitatively fitted surgical style N95 filtering facepiece respirator device to extreme reuse and extended wear conditions (up to 19 uses over a duration of 5 days) and measured its protective performance at regular intervals, including simulated workplace protection factor measurements using total inward leakage. With this respirator, it was shown to be possible to maintain protection corresponding to an assigned protection factor greater than 10 under extreme usage conditions provided an individual is properly trained in the use of, and expertly fitted in, the respirator. Other factors such as hygiene and strap breakage are likely to place limits on reuse.
大多数在医疗保健环境中使用的呼吸器，以及在第一响应者和工业环境中经常使用的呼吸器，都是一次性使用的：使用者戴上呼吸器，进行一项工作活动，然后脱下并丢弃呼吸器。然而，在当前的 COVID-19 大流行中，由于个人防护设备持续短缺，许多医疗保健组织经常考虑延长和重复使用过滤式面罩呼吸器。此外，目前正在进行大量研究以了解消毒对重复使用可能性的影响，并对性能进行了一些调查。虽然这种呼吸器在经过多次消毒循环后继续提供有效保护的能力是实施重复使用的关键组成部分，但同样重要的是要了解在工作期间多次重复使用呼吸器，甚至延长其佩戴时间，对工作场所保护性能的影响。在这项研究中，我们对库存的定量适配的外科风格 N95 过滤式面罩呼吸器设备进行了极端重复使用和延长佩戴条件（长达 5 天内使用 19 次）的测试，并定期测量其保护性能，包括使用总向内泄漏进行模拟工作场所保护因数测量。结果表明，在极端使用条件下，只要个人经过正确的使用培训并在呼吸器的适配方面经验丰富，就有可能保持对应于分配保护因数大于 10 的保护。其他因素，如卫生和表带断裂，可能会限制重复使用。
