Fabric, surgical masks only 10% effective against COVID-19: study

An alarming new study from the University of Waterloo in Canada has found that fabric and surgical masks are only 10% effective in protecting the wearer from aerosols dispersed by people infected with COVID-19, Daily mail reported on Saturday.

“There is no doubt that it is beneficial to wear a face covering, both to protect yourself near and from a distance in a room,” said study leader Serhiy Yarusevych, professor of engineering. mechanics and mechatronics, in a press release.

“However, there is a very serious difference in the effectiveness of different masks when it comes to controlling aerosols,” he said.

The study involved experiments using a mannequin to simulate a person sitting in a large room and breathing.

It has been found that there is a significant build-up over time of aerosol droplets – tiny particles exhaled by people that remain suspended and travel through the air – despite the use of surgical clothing and masks. currents.

A previous study had determined that these droplets scattered by infected people transmit the virus even outside the two-meter social distancing zone recommended by health experts.

The new study found that common masks aren’t as effective, mainly due to fit issues. Therefore, they are only able to filter out 10% of exhaled aerosol droplets. The remaining droplets escape through the top of the mask where it sits over the nose and into the air, unfiltered.

In comparison, the higher quality N95 and KN95 masks filter over 50% of exhaled aerosols that remain in the air indoors and can be inhaled by other people.

Yarusevych said that the greater effectiveness of these masks compared to fabric and surgical masks “shows a compelling argument that they should be worn in indoor environments, such as schools and workplaces, whenever possible,” reported Daily mail.

“A lot of this may sound like common sense,” he said. “There’s a reason, for example, why doctors wear N95 masks – they work much better. The novelty here is that we have provided solid numbers and rigorous analysis to support this hypothesis. “