Innovative Self-Sterilisation Desiccant Masks (SterilMask)

新冠肺炎通过受感染的分泌物或其呼吸道飞沫与感染者直接、间接或密切接触而传播。这可以通过口罩来限制。现在建议在适当的社交距离难以维持的情况下使用面罩。保护一线卫生工作者是最重要的，个人防护装备(PPE)必须优先考虑。然而，尽管使用了PPE，但仍有大量医护人员被感染或失去生命。此外，包括口罩在内的医疗环境中的个人防护用品在全球范围内短缺。常用的一次性医用外科口罩和FFP 3/N95口罩对新冠肺炎有一定的保护作用，但在病毒浓度高的情况下效果不是很好，每次使用后都需要更换以避免污染。为了解决口罩短缺的问题，人们设计了不同的方法来对一次性口罩进行消毒、清洁和消毒。由于口罩的内部和外部都可能含有呼吸道分泌物，因此在重复使用之前，有效地净化口罩是很重要的。医院有清洗口罩的程序，但通常很耗时，涉及不同类型的气体和特殊机器。一次性口罩是由无纺布制成的；FFP3/N95口罩不能安全地清洗以供重复使用，因为暴露在过量的水和清洁产品中会破坏纤维并损害碳过滤系统。有效去除口罩污染的最佳方法仍在研究中，但初步证据发现，冠状病毒的痕迹在口罩上持续存在相当长的时间，这表明口罩的持续消毒对于更好的保护至关重要，特别是对医疗设施。在这个项目中，一种自杀菌干燥剂口罩被提出，它使用高效的干燥剂材料(盐)来持续杀菌，而不会损害口罩的过滤能力和透气性。与使用消毒材料或其他设备/工具不同，灭菌口罩提供自我消毒性能，以有效地净化口罩，其中干燥材料杀死/灭活口罩皮肤和吸入空气中的病毒。干燥剂材料可以用多孔膜布包裹，形成面膜。或者，可以使用由浸渍的干燥剂材料制成的干燥剂薄片与布片层叠在一起的膜片作为面具。另一种选择是使用膜片作为可回收塑料制成的无菌口罩的盖子。这种干燥剂可以湿化进入鼻腔和鼻窦腔的吸入空气，降低湿度/最大限度地减少凝结，为佩戴者提供更好的舒适性。无菌口罩可以提供持久的消毒效果。此外，不需要再生干燥剂材料/片材，因为吸入和呼出的空气之间的湿度水平的差异可以有助于自我平衡性能。SterilMASK可以加入额外的过滤器，以增强透气性，并为长期佩戴的人提供更好的舒适性，如医疗保健人员和工厂工人。先进且实惠的SterilMASK将提供安全和增强的呼吸体验，以及耐用性、可回收和可重复使用的特性。使用消毒口罩将大大减少数百万被丢弃的一次性口罩的浪费。

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.