The use of face masks in public places is one of the core recommendations featured in coronavirus guidelines since the COVID-19 pandemic started to spread across the world. However, the number of guidelines related to the construction and materials used for manufacturing face masks is quite low.
A new study created by researchers from the Florida Atlantic University sought to learn more about the materials used for creating face masks and their capacity to capture and control droplets that could facilitate the spread of the virus.
The team of researchers analyzed several materials and potential design choices to see how efficient they are at preventing the droplets from escaping the mouth. With the help of a high-power laser, the team observed droplets that were being coughed and sneezed with the help of an array mounted inside a mannequin head.
According to the lead researcher, there were a few studies focused on the efficiency of surgical-grade medical equipment, but researchers don’t have a lot of information about cloth-based face masks, which tend to be quite popular among some users, with many describing them as more breathable.
Recreating accurate conditions
While the laser sheet setup has been used in the case of many fluid mechanics experiments, the main challenge faced by the researchers is to create an accurate representation of a sneeze or cough, and they had to employ a simplified cough.
Home-made masks which contained several layers of quilting materials and cone-style masks sold at shops were among the most efficient according to the results, as they reduced the number of droplets by an impressive margin. On the other hand, face masks that were folded poorly and lose bandanas reduced droplets jets by a mere 1/8. Without masks, droplets managed to cover more than 6 feet (or one and a half meters).
More data can be found in the study, which was published in a scientific journal.