The duo cited several data to point out that at places where wearing masks was mandated and duly followed, the incidence of transmission of coronavirus declined.
Masks and protection from coronavirus: Two scientists have issued clarifications regarding the use of masks and their efficacy during the ongoing coronavirus pandemic, recommending people to wear two masks instead of one in certain situations. The scientists also asserted that masks play an important role in protecting not only people around the wearer, but also the wearer themself. The attempt to clear up any confusion has been made by Monica Gandhi of San Francisco-based University of California, and Virginia Institute of Technology’s Linsey Marr in a commentary for Cell journal, which has been accessed by Financial Express Online.
Coronavirus pandemic: How masks work
Gandhi and Marr explained that masks do not work like sieves, filtering out droplets that are too large to pass through the holes. Instead, the individual, tightly packed fibres of the material force air flow to curve around them, much like an obstacle course. However, the aerosols cannot bend sharply like the air, and end up either slamming against the fibre or coming too close to the fibre and sticking to it. Meanwhile, very small aerosols crash against the fibre after acquiring random motion from air molecules that bounce off them.
This process works both ways, according to the flow of the air as the wearer inhales and exhales, the duo said.
Coronavirus and masks: Recommendations
The duo has recommended that the people wear a fabric mask with at least two layers of cloth having high thread count or a high-quality surgical mask. These suggestions, however, are for basic protection.
Gandhi and Marr have also recommended the masks people should wear for maximum protection:
- People can wear a surgical mask and on top of it, a cloth mask tightly. In this arrangement, the surgical mask acts as a filter, while the cloth mask helps in improving the fit of the masks, while also acting as an additional safety layer.
- People can also choose to wear a three-layered mask, in which the middle layer is made of a non-woven high-efficiency filter material, while the outer layer is made of flexible and tightly woven fabric that can conform to the face well.
The duo said that if in these arrangements, the masks fit the wearer well, it could produce an overall efficiency of more than 90%.