As the Covid-19 pandemic started to take hold last year, the health officials recommended using a face mask to prevent exposure to coronavirus. While all health experts suggest that cloth masks are better than not using any mask to cover the face, there were concerns regarding the safety levels assuming they are ineffective for coronavirus. A new study published by the research team from the Universities of Bristol in collaboration with Surrey has tried to investigate the protection level provided by cloth masks for effective prevention of coronavirus entry to the nasal cavity.
The results indicated that any properly fitted, three-layer cloth mask is as helpful as a surgical-grade mask to reduce the transmission rate. These complete results are now published in the journal the Physics of Fluids.
U.S Centers for Disease Control and Prevention (CDC) urges everyone to use a face covering while in public. Using a face covering hinders the entry and transmission of the virus; not only it protect catching coronavirus but also reduces transmitting the virus to others through exhalation.
In this study, the researchers evaluated the entrance and filtration of liquid droplets containing viral particles through cloth masks. They also studied inertial impaction which is different from filtration through a sieve or even the colander. This inertial impact provided by the cloth masks forces the air to twist, creating a different path for the droplets to travel. Once they change their way, the cloth fiber traps them eventually preventing inhalation.
In ideal conditions, i.e., using a properly fitted mask and layered cloth mask, cloth masks are more or less similar to the surgical mask sharing the same mechanism for filtering droplets having coronavirus particles. Both these types of masks provide between 50% to 75% efficacy.
It means if an infected person and a healthy, covid-free person are wearing masks, the chances to prevent viral entry among them are up to 94% efficient. Dr. Richard Sear from the University of Surrey is the main researcher and co-author of this study. He heads the Soft Matter Research Group at the university.
According to him, cloth masks are relatively simple and inexpensive than surgical-grade masks. Contrary to previous assumptions, cloth masks are equally helpful in reducing coronavirus exposure and transmission. He further added that his theoretical model has confirmed the efficacy of cloth masks however, it is necessary to use a proper cloth mask that contains three layers and properly fits the face.
This study may provide face mask designs to change and popularizing the use of cloth face masks. Not only it will clear the confusions that may show up in people regarding protection from the virus but also prevents the face mask shortage that showed up in the early days of the pandemic, and making the surgical grade masks available for the medical staff and healthcare workers.
Remember, these results only apply to the factory-made cloth masks and not the homemade masks or using cloth i.e. scarf, bandana, etc to cover the face and expecting it to save from coronavirus.