Innovative Self-Sterilisation Desiccant Masks (SterilMask)

COVID-19的传播是通过直接、间接或密切接触感染者的分泌物或其呼吸道飞沫进行的。这可以用口罩来限制。现在，当难以保持适当的社交距离时，建议使用面部覆盖物。对一线卫生工作者的保护至关重要，必须优先考虑个人防护设备。然而，尽管使用PPE，仍有大量医护人员被感染或丧生。此外，全球医疗场所的个人防护设备短缺，包括口罩。常用的一次性医用外科口罩和FFP 3/N95口罩对COVID-19有一定的防护作用，但在高病毒浓度下效果不佳，需要在每次使用后更换，以避免污染。为解决口罩短缺的问题，我们设计了不同的方法来消毒、清洁和灭菌一次性口罩。由于口罩的内外都可能含有呼吸道分泌物，因此在重复使用口罩之前，有效地对口罩进行消毒非常重要。医院有清洗口罩的流程，但通常都很耗时，涉及不同类型的气体和特殊机器。一次性口罩由无纺布制成; FFP 3/N95口罩不能安全地清洁以重复使用，因为暴露于过量的水和清洁产品会破坏纤维并损坏碳过滤系统。有效消毒口罩的最佳方法仍在研究中，但初步证据显示，冠状病毒的痕迹在口罩上持续存在了相当长的时间，这表明口罩的持续消毒对更好的保护至关重要，特别是对医疗设施。在这个项目中，提出了一种自我消毒的干燥剂口罩“SterilMask”，其使用高效干燥剂材料（盐）进行连续消毒，而不损害面罩的过滤能力和透气性。SterilMask不使用消毒材料或额外的设备/工具，而是提供自消毒特性，以有效地净化面罩，其中干燥剂材料杀死/灭活面罩皮肤上和吸入空气中的病毒。干燥剂材料可以用多孔膜织物封装以形成掩模。可替代地，由浸渍干燥剂材料制成的干燥剂片在与织物片层叠的膜片上可以用作掩模。另一种选择是使用膜片作为由可回收塑料制成的SterilMask的覆盖物。干燥剂可以加湿进入鼻腔和鼻窦腔的吸入空气，降低水分水平/最大限度地减少冷凝，为佩戴者提供更好的舒适度。SterilMask可以提供持久的杀菌效果。此外，不需要干燥剂材料/片材的再生，因为吸入和呼出空气之间的湿度水平的差异可能有助于自平衡性能。SterilMask可以增加一个额外的过滤器，以提高透气性，并为长期佩戴者提供更好的舒适度，如医护人员和工厂工人。先进和负担得起的SterilMask将提供安全和增强的呼吸体验，以及耐用性，可回收性和可重复使用性。SterilMask的使用将大大减少数百万个一次性口罩的浪费。

Transmission of COVID-19 occurs through direct, indirect, or close contact with infected people through infected secretions or their respiratory droplets. This can be limited with face masks. Face coverings are now recommended where appropriate social distancing could be difficult to maintain. The protection of frontline health workers is paramount and personal protective equipment (PPE) must be prioritized. However, large numbers of healthcare workers have been infected or lost their lives in spite of using PPEs. Moreover, there is a global shortage of PPE for medical settings, including face masks. Commonly used disposable medical surgical mask and FFP3/N95 mask provide some protection against COVID-19 but are not very effective in high virus concentrations and need to be replaced after each use to avoid contamination.To address the scarcity of face mask, different approaches have been conceived to disinfect, clean, and sterilise the disposal masks. Since a mask can contain respiratory secretions on both the inside and outside, it is important to effectively decontaminate the mask before reusing it. There are processes in hospitals for cleaning masks, but typically they are time-consuming, involving different types of gases and special machines. Disposable masks are made from non-woven fabrics; FFP3/N95 masks cannot be safely cleaned for reuse since exposure to excessive amounts of water and cleaning products destroys the fibres and damages the carbon filtration systems. Optimum practices for effectively decontaminating masks are still being researched, yet preliminary evidence finds traces of the coronavirus persisted for considerable time on masks, which indicates that continuous sterilisation of face masks is essential for better protection, especially for healthcare facilities.In this project, a self-sterilising desiccant mask, 'SterilMask' is proposed, which uses highly efficient desiccant material (salts) for continuous sterilisation without damaging the mask's filtration capability and breathability. Instead of using disinfecting materials or additional equipment/tools, SterilMask provides self-sterilisation properties to efficiently decontaminate the mask where the desiccant material kills/deactivates viruses on the mask skin and in the inhaled air. The desiccant material can be encapsulated with porous membrane fabrics to form into a mask. Alternatively, a desiccant sheet made of an impregnated desiccant material onto a membrane sheet layered with a fabric sheet can be used as a mask. Another option is to use the membrane sheet as a cover for SterilMask made from recyclable plastics. The desiccant can humidify inhaled air passing into the nose and sinus cavities, reducing the moisture level/minimising condensation, providing better comfort for wearers. SterilMask can provide long-lasting sterilisation effect. Furthermore, regeneration of the desiccant material/sheet is not needed because the difference in the humidity levels between the inhaled and exhaled air could contribute to the self-balanced performance. An additional filter can be incorporated to SterilMask to enhance breathability, and provide improved comfort for long-period wearers, such as healthcare workers and factory workers.The advanced and affordable SterilMask will provide safety and enhanced breathing experience, and durability, recyclability, and reusability features. The use of SterilMask would significantly reduce the waste of millions of disposed single-use masks.