Double masking gives more protection

Wearing two overlapping masks or a tight-fitting surgical mask offers enhanced protection against the spread of the coronavirus through the air, according to a study by US health authorities published this Wednesday, February 10.

The mask significantly reduces the exhalation of small droplets by infected people and reduces exposure to these particles for uncontaminated people, recalls the US Centers for Disease Control and Prevention (CDC,). ) in this studio.

But cloth and surgical masks tend to fit looser than KN95 (or FFP2), increasing the risk of air escaping from the sides.

In January, the CDC ran laboratory simulations to test leak reduction with a cloth mask overlying a surgical mask, and then a surgical mask with rubber bands knotted near the edges that folded inward.

In another experiment, it was found that exposure to an infected person who does not wear a mask is reduced by 83% with a double mask and by 64.5% with a face-tight or plastic mask, or with a nylon protector over a surgical mask.

“That means that these masks work and that they do better when they are fitted and worn correctly,” said Rochelle Walensky, the director of the CDC, during a press conference.

CDC will update its public information on masks with these new options.

At a time when new, more contagious variants of the coronavirus are spreading across the United States, these experiments come to support previous studies on the need to wear better quality masks, respecting stricter standards, or overlapping masks.