BACKGROUND Face masks, also referred to as half masks, are essential to protect healthcare professionals working in close contact with patients with COVID-19-related symptoms. Because of the Corona material shortages, healthcare institutions sought an approach to reuse face masks or to purchase new, imported masks. The filter quality of these masks remained unclear. Therefore, the aim of this study was to assess the quality of sterilized and imported FFP2/KN95 face masks. METHODS A 48-minute steam sterilization process of single-use FFP2/KN95 face masks with a 15 minute holding time at 121°C was developed, validated and implemented in the Central Sterilization Departments (CSSD) of 19 different hospitals. Masks sterilized by steam and H2O2 plasma as well as new, imported masks were tested for particle filtration efficiency (PFE) and pressure drop in a custom-made test setup. RESULTS The results of 84 masks tested on the PFE dry particle test setup showed differences of 2.3±2% (mean±SD). Test data showed that the mean PFE values of 444 sterilized FFP2 face masks from the 19 CSSDs were 90±11% (mean±SD), and those of 474 new, imported KN95/FFP2 face masks were 83±16% (mean±SD). Differences in PFE of masks received from different sterilization departments were found. CONCLUSION Face masks can be reprocessed with 121 °C steam or H2O2 plasma sterilization with a minimal reduction in PFE. PFE comparison between filter material of sterilized masks and new, imported masks indicates that the filter material of most reprocessed masks of high quality brands can outperform new, imported face masks of unknown brands. Although the PFE of tested face masks from different sterilization departments remained efficient, using different types of sterilization equipment, can result in different PFE outcomes.

中文翻译：

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一次性口罩灭菌能否替代进口口罩？在 COVID-19 短缺期间，包括 19 个消毒部门和 471 个进口品牌类型在内的全国性实地研究。

背景口罩，也称为半面罩，对于保护与 COVID-19 相关症状患者密切接触的医疗保健专业人员至关重要。由于电晕材料短缺，医疗机构寻求一种方法来重复使用口罩或购买新的进口口罩。这些口罩的过滤质量仍不清楚。因此，本研究的目的是评估经过消毒和进口的FFP2/KN95口罩的质量。方法 在 19 家不同医院的中央消毒部门 (CSSD) 中开发、验证并实施了一次性 FFP2/KN95 口罩的 48 分钟蒸汽消毒工艺，并在 121°C 下保持 15 分钟。蒸汽和 H2O2 等离子体消毒的口罩以及新的、进口口罩在定制的测试装置中进行了颗粒过滤效率 (PFE) 和压降测试。结果 在 PFE 干粒子测试装置上测试的 84 个口罩的结果显示差异为 2.3±2%（平均值±SD）。检测数据显示，19家CSSD中444只经过消毒的FFP2口罩的平均PFE值为90±11%（平均值±SD），474只新进口的KN95/FFP2口罩的PFE平均值为83±16%（平均值±SD）。 ）。发现从不同消毒部门收到的口罩的 PFE 存在差异。结论 面罩可以使用 121 °C 蒸汽或 H2O2 等离子消毒进行再处理，同时 PFE 的降低最小。灭菌口罩过滤材料与新进口口罩的PFE对比表明，大多数优质品牌再加工口罩的过滤材料性能优于未知品牌的新进口口罩。