Development of Custom and One-Size-Fits-All Masks for COVID-19 Personal Protection

NSERC联盟与阿尔伯塔省先进MNT产品中心（ACAMP）合作开展的COVID-19项目的总体目标是为加拿大一线卫生保健工作者和公众提供可持续性的呼吸器选择，并提高其可用性。由于目前的一次性选择导致供应短缺，并因不合适而对许多卫生保健工作者造成皮肤创伤，因此研究提供改进可用性的可重复使用选择至关重要。我们将开发自定义和一刀切的方法来生成掩模几何，并研究这两种方法的优点和局限性。我们项目的第一个目标将是开发体外和体内实验室方法来定量评估呼吸器的性能。体外方法将利用带有称重传感器的塑料面部模型来测量力和过滤水平，允许过滤和施加在模拟面部上的力的相关性。体内测试将涉及人类志愿者，使用类似的过滤测量和感知个人舒适度，以进一步了解口罩性能，包括口罩/组织界面。然后，我们将利用这些开发的实验室方法来研究定制和一刀切的口罩的性能，以推动进一步的改进。尽管有增材制造路线来生产定制医用级硅胶口罩密封件，但我们尚未调整生产变量（例如化学成分）以优化应用性能。在考虑一刀切的口罩时，我们的目标是优化口罩的几何形状，以增加使用的舒适性。我们对定制方法和一刀切方法的比较将提供有价值的见解，以了解这两种方法的优点和局限性，从而更好地确定实际使用选项（例如，戴着口罩去买杂货与在医院轮班12小时）。通过该项目开发的可重复使用的N95口罩将改善加拿大一线医护人员在COVID-19大流行期间的工作条件，并为公众提供更可持续的选择，以减少病毒传播。

The overarching objective of this NSERC Alliance COVID-19 project in partnership with the Alberta Centre for Advanced MNT Products (ACAMP) is to produce sustainable respirator options with improved usability for Canadian frontline health care workers and general public. With current disposable options resulting in supply shortages and causing skin trauma on many health care workers through improper fit, research towards providing reusable options with improved usability is critical. We will develop custom and one-size-fits-all approaches for generating mask geometry and investigate the advantages and limitations of both approaches. Our first objective of the project will be to develop in vitro and in vivo laboratory methods to quantitatively evaluate respirator performance. In vitro methods will utilize plastic face models instrumented with load cells to measure force and filtration level, allowing for correlation of filtration and force exerted on simulated faces. In vivo tests will then involve human volunteers using similar filtration measurements alongside perceived personal comfort to provide further insight into mask performance including the mask/tissue interface. We will then utilize these developed lab methods to investigate the performance of custom and one-size-fits-all masks to drive further improvement. Despite having an additive manufacturing route for producing custom medical grade silicone mask seals, we have yet to tune production variables (e.g. chemical composition) to optimize performance in application. When considering one-size-fits-all masks, we will aim to optimize mask geometry to increase comfort in use. Our comparisons between custom and one-size-fits-all approaches will provide valuable insight to understand the advantages and limitations of both approaches to better identify practical usage options (e.g. wearing a mask to get groceries vs. a 12-hour hospital shift). The reusable N95 respirator options to be developed through this project will improve working conditions for Canadian frontline health care workers during the COVID-19 pandemic and provide more sustainable options for the general public to reduce viral transmission.