Protect yourself from Covid with three-layer masks: The Tribune India

New Delhi, March 6

When buying a new face mask to protect yourself from Covid-19 infection, be sure to go for a three-layer mask as it is more effective than one- or two-layer alternatives, pointed out health experts Saturday.

According to experts, additional layers in the mask can help protect us against SARS-CoV-2 by not allowing contagious virus-laden droplets or particles to pass through the mask.

“Covid-19 is spread primarily through respiratory droplets which are produced when someone who has contracted the virus from coughing, sneezing, etc.,” said Navneet Sood, pulmonology consultant at Dharamshila Narayana Superspeciality Hospital.

“As we know that the layers of a mask help to increase its filtering power, it becomes crucial to wear a three-layer mask, so that we can protect ourselves against infection or the infection of people around us” , Sood added.

A team of researchers including Saptarshi Basu from the Indian Institute of Science, Bengaluru and Abhishek Saha from the University of California – San Diego have shown, in a study, that three-layer surgical masks are the most effective in stopping large droplets from a cough or sneeze so as not to be atomized into smaller droplets.

These large cough droplets can penetrate through one- or two-layer masks and atomize into much smaller droplets, which is especially crucial because these smaller droplets (often called aerosols) can linger in the air for longer. long periods of time.

“While large solid particles on the order of 500-600 microns are expected to be stopped by a single-layer mask with an average pore size of 30 microns, we show that this is not the case. case for liquid droplets, ”Saha said.

“If these large respiratory droplets have sufficient velocity, which happens with coughing or sneezing, when they land on a single layer of this material, they disperse and squeeze through the smaller pores of the mask,” he added.

For the study, published in the journal Science Advances, the team used a droplet generator and a high-speed accelerated camera.

According to the Centers for Disease Control and Prevention (CDC), when selecting a mask, always opt for masks – with at least two layers of washable, breathable fabric, which completely cover your nose and mouth, which fit perfectly to the sides of your face and have no gaps.

“You should know that not all fabrics constitute an effective mask. Also, some tissues are not suitable for certain skin types and the way they are woven is another factor, ”said Shiba Kalyan Biswal, consultant, Lung and Sleep Medicine, Narayana Hospital, Gurugram.

“One should opt for masks with small pores because they can better protect against the virus by not helping virus-laden droplets or participles to pass through. After purchase, maintaining their cleanliness is also a key factor. “, added Biswal.

Health experts have also warned that we need to be more careful as cases of new strains of Covid are gradually increasing in the country.

They expressed a number of possibilities that could be due to people’s lax attitude towards adhering to Covid protocols or sympathy for the “mutations and new strains” causing the outbreak, as has been investigated by laboratories involved in the detection of Covid across the country. .

Various studies have cited that a variant of SARS-CoV-2 that emerged in the UK – B.1.1.7 – in November 2020 is more transmissible than the pre-existing variants and will lead to a strong resurgence of Covid-19 cases. IANS