LaRue Ryan J, Morkus Patrick, Laengert Scott, Rassenberg Sarah, Halali Mohamad Amin, Colenbrander John W, Clase Catherine M, Latulippe David R, de Lannoy Charles-François
Centre of Excellence in Protective Equipment and Materials (CEPEM) 1280 Main St. W. Hamilton ON Canada.
McMaster University Department of Chemical Engineering Canada.
Glob Chall. 2021 Aug 5;5(11):2100052. doi: 10.1002/gch2.202100052. eCollection 2021 Nov.
Public health agencies have recommended the community use of face masks to reduce the transmission of airborne diseases like COVID-19. Virus transmission is reduced when masks act as efficient filters, thus evaluating mask particle filtration efficiency (PFE) is essential. However, the high cost and long lead times associated with purchasing turn-key PFE systems or hiring certified laboratories hampers the testing of filter materials. There is a clear need for "custom" PFE test systems; however, the variety of standards that prescribe (medical) face mask PFE testing (e.g., ASTM International, NIOSH) vary widely in their protocols and clarity of guidelines. Herein, the development is described of an "in-house" PFE system and method for testing face masks in the context of current standards for medical masks. Pursuant to the ASTM International standards, the system uses an aerosol of latex spheres (0.1 µm nominal size) with particle concentrations upstream and downstream of the mask material measured using a laser particle analyzer. PFE measurements are obtained for a variety of common fabrics and medical masks. The approach described in this work conforms to the current standards for PFE testing while providing the flexibility to adapt to changing needs and filtration conditions.
公共卫生机构建议社区使用口罩，以减少 COVID-19 等空气传播疾病的传播。当口罩作为高效过滤器时，病毒传播会减少，因此评估口罩的颗粒过滤效率（PFE）至关重要。然而，购买交钥匙 PFE 系统或聘请认证实验室的高成本和长交付周期阻碍了过滤材料的测试。显然需要“定制”PFE 测试系统；然而，规定（医用）口罩 PFE 测试的各种标准（例如 ASTM 国际、美国国家职业安全与健康研究所）在其协议和指南的清晰度方面差异很大。在此描述了一种“内部”PFE 系统和方法的开发，用于在医用口罩现行标准的背景下测试口罩。根据 ASTM 国际标准，该系统使用乳胶球气溶胶（标称尺寸为 0.1 µm），通过激光粒子分析仪测量口罩材料上游和下游的颗粒浓度。对各种常见织物和医用口罩进行了 PFE 测量。这项工作中描述的方法符合 PFE 测试的现行标准，同时提供了适应不断变化的需求和过滤条件的灵活性。
