![]() ![]() Masks prevent the release of most small respiratory droplets into the air by slowing the particles as they pass through the mask, facilitating their interception by fabric fibers. Does this mean that face masks don’t prevent the passage of smaller particles? Not so. Such droplets are known as droplet nuclei and form a small cloud in the air known as an aerosol.Ī study published in June 2021 found that the average pore diameters for reusable face masks, surgical masks and N95 masks are 47, 33 and 30 micrometers, respectively, based on X-ray tomography analysis. On the other hand, smaller droplets with a diameter of five micrometers (1 millionth of a meter) or less can remain suspended in the air for minutes to hours. They can therefore only be transmitted over short distances. Because of their size and weight, such droplets fall quickly to the ground in seconds to minutes. Centers for Disease Control and Prevention (CDC) explains, large droplets are those with a diameter greater than five micrometers. These droplets are classified into two groups according to their size and the way they move through the air.Īs the website of the U.S. Viruses such as SARS-CoV-2 are transmitted through the air by small respiratory droplets, which are expelled when people cough, talk, sneeze or breathe. How face masks prevent airborne disease transmission However, contrary to what is claimed in these videos, face masks are an effective measure for preventing COVID-19 transmission, as we explain in this review. This video received almost 4,000 interactions on Facebook at the time of this review’s writing, including more than 1,200 shares. Wheeler claimed that face masks aren’t effective in preventing COVID-19 infections, citing several studies that found no benefit from the use of face masks. Other videos have also questioned the effectiveness of face masks, such as this one posted by political commentator Liz Wheeler on 4 August 2021. The video accumulated more than 35,000 interactions on Facebook at the time of this review’s writing, including more than 13,000 shares, according to social media analytics tool CrowdTangle. To support his argument, Bridle put on five surgical masks and showed the condensation of water vapor that his breath left on his glasses through the masks. In the video, Bridle argued that the pores in the fabric of face masks are larger than respiratory droplets, and that these therefore pass through the masks and can spread viral particles. In late April 2021, a video was published by the YouTube channel Net Nuance, in which immunologist Byram Bridle questioned the efficacy of surgical masks. This is known as source control.ĭifferent arguments that questioned the usefulness or safety of face masks have been refuted in previous Health Feedback reviews, such as this one explaining that respiratory droplets are blocked by cloth masks, or this one explaining that face masks don’t prevent the passage of air and therefore can’t cause health problems associated with lack of oxygen or carbon dioxide buildup in the blood. Face masks prevent most of these droplets from being released into the air, thus reducing the release of infectious material that could reach other people. ![]() COVID-19 is transmitted mainly through respiratory droplets from infected people, which are expelled when coughing, talking or breathing. Multiple scientific studies have shown that mask-wearing is effective in reducing the number of infections. ![]() The wearing of face masks is one of the public health measures that has been adopted to reduce the spread of COVID-19. FULL CLAIM: Pores in the fabric of face masks are larger than viral particles and aerosols expelled when breathing, so they don’t block their passage Face masks don’t prevent the transmission of COVID-19 “The science itself debunks the use of face masks to stop viruses like COVID-19” “The CDC admitted they don’t have any randomized control trials that support face mask mandates for COVID-19”. Centers for Disease Control and Prevention and the European Centre for Disease Prevention and Control. There is also evidence that face masks are effective in preventing the transmission of COVID-19, so their use by the general population has been recommended by various public health agencies such as the U.S. Face masks filter small airborne particles which carry viral particles, including respiratory droplets, even if these particles are smaller than the pore size of face masks, as small airborne particles do not move in a straight line and collide with the fabric fibers while passing through the mask. ![]()
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