A BioEngineering approach for the SAFE design and fitting of Respiratory Protective Equipment (BE-SAFE RPE)

呼吸防护设备（RPE）被广泛用于限制病毒和细菌的传播，是控制COVID-19的关键手段。特别是FFP 3/N95型呼吸器口罩，最初设计用于防止空气中的灰尘颗粒，已广泛用于保护医护人员（图1）。至关重要的是，这些口罩紧密贴合面部，以形成气密密封，并通过贴合测试进行检查。然而，这些面罩通常是为白色男性劳动力设计的，提供了有限的尺寸和几何形状范围。这可能会导致过度拧紧以补偿与软组织损伤相关的不佳贴合性，并增加感染风险。这个多学科项目将研究RPE设备的适合性和生物力学，以确保为用户提供安全的界面。计算建模和MRI将用于探索面部软组织如何在与面罩接触时变形。这些模型将通过实验监测RPE应用期间的机械和热负荷以及局部皮肤生理学的相关变化来了解。此外，该项目将利用现有的脸型数据库，调查面具对更具代表性的用户范围的适合性。这将导致开发新口罩的设计模板（与英国制造商合作），标准测试方法（STM）以评估面部损伤的风险（与测试和标准组织合作），以及智能适配软件以确保用户选择正确的口罩。

Respiratory protective equipment (RPE) is widely used to limit the transmission of viruses and bacteria, representing a critical means of controlling Covid-19. In particular, respirator masks of the FFP3/N95 types, originally designed to protect against airborne dust particles, have been widely used to protect healthcare workers (Fig 1). It is essential that these masks fit tightly against the face to make an airtight seal, checked by fit testing. However, these masks are typically designed for a white male workforce, providing a limited range of size and geometry. This can lead to overtightening to compensate for a poor fit, which is associated with soft tissue injuries, as well as an increased risk of infection. This multidisciplinary project will investigate the fit and biomechanics of RPE devices, to ensure provision of a safe interface with users. Computational modelling and MRI will be used to explore how the soft tissues of the face deform in contact with a mask. These models will be informed through experimental monitoring of mechanical and thermal loads during RPE application and the associated changes in local skin physiology. In addition, the project will utilise existing databases of face shapes to investigate the fit of masks on a more representative range of users. This will lead to the development of design templates for new masks (working with UK manufacturers), standard test methods (STMs) to evaluate the risk of facial injury (working with testing and standards organisations), and intelligent fitting software to ensure that users select the correct mask.