Particle-filtering face masks are designed to protect against various (droplet) infections, such as COVID-19 and others. The viruses that settle in the respiratory tract of an infected person become airborne through fine infectious droplets when sneezing, coughing, or speaking, but also when breathing itself, and can thus be inhaled by other people.

Face seal leakage plays a significant role in estimating the protection efficiency provided by face masks. Thus, there is a risk to be infected with a certified face mask. This work aims to quantify the air and particle leakages through face seal for three different types of FFP2 face masks. This was realised using Computational Fluid Dynamics (CFD) simulations.

To reveal the spots where main leakage occurs, a Sheffield test head fitted with three face masks of different shape (Fig. 1) was scanned using a microcomputed tomography (µCT). The tomographic images showed that the greatest leakage zones are located in the vicinity of the nose. Based on the obtained form (µCT) geometries, computational meshes were generated for CFD simulations.

Particle-filtering face masks are designed to protect against various (droplet) infections, such as COVID-19 and others. The viruses that settle in the respiratory tract of an infected person become airborne through fine infectious droplets when sneezing, coughing, or speaking, but also when breathing itself, and can thus be inhaled by other people.

Face seal leakage plays a significant role in estimating the protection efficiency provided by face masks. Thus, there is a risk to be infected with a certified face mask. This work aims to quantify the air and particle leakages through face seal for three different types of FFP2 face masks. This was realised using Computational Fluid Dynamics (CFD) simulations.

To reveal the spots where main leakage occurs, a Sheffield test head fitted with three face masks of different shape (Fig. 1) was scanned using a microcomputed tomography (µCT). The tomographic images showed that the greatest leakage zones are located in the vicinity of the nose. Based on the obtained form (µCT) geometries, computational meshes were generated for CFD simulations.

Particles were then simulated in addition to the air flow, using sodium chloride in a size range from 10 to 500 nm. Simulations showed that ...