Since the start of the Covid-19 pandemic, the object that has attracted the most attention has undoubtedly been the protective mask. Recently, a study compared different shapes and materials. The goal? Determine in case of sneezing and coughing the best mask configuration that limits the spread of the virus the most.
The mask is currently the main tool for limiting the spread of the coronavirus. In the past, several studies have ruled on the performance of medical-grade masks. On the other hand, the data on the materials and the shape of the masks made by the general public are almost non-existent. A study conducted by the University of Florida Atlantic (USA) and published in the journal Physics of Fluids June 30, 2020 was rightly interested in the subject.
As part of this research, it was a question of visualizing through several masks the propagation of droplets carrying SARS-CoV-2. It should be remembered in passing that this is the main means of transmission of the various coronaviruses. Thus, the American researchers reproduced sneezes and coughs using a dummy and then took photographs of the particles highlighted with a laser.
The study leaders tested several types of masks. These are different handmade masks, a non-sterile conical mask sold in pharmacies and a simple bandana. According to the results, the bandana and the handmade mask made of double-folded cloth handkerchief do not offer sufficient protection. On the other hand, the conical mask performs much better, as does the handmade mask from two layers of tight cotton.
The experiment made it possible to measure the distance of propagation droplets according to the different materials (and shapes). First of all, let's mention the fact that a sneeze without a mask is the cause of projections up to 2.5 m. This value is 1.1 m for the bandana and 38 cm for the fabric mask, which is still too much. However, the conical mask sold in pharmacies does not project droplets more than 20 cm away, which is already much better. Finally, the palm goes to the tight cotton mask, reducing the distance to only 6 cm.
In sum, handmade masks can sometimes be more effective than some masks sold commercially. However, it is essential to work on the shape and especially the materials for good efficiency.
