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The examples and perspective in this deal primarily with the United States and do not represent a worldwide view of the subject. You may improve this, discuss the issue on the talk page, or create a new, as appropriate. February 2022 Learn how and when to remove this template message. US Ambassador to Indonesia Sung Kim accompanied by local officials at the Presidential Palace wearing face masks amid the COVID-19 pandemic. During the COVID-19 pandemic, face masks, such as surgical masks and cloth masks, have been employed as a public and personal health control measure against the spread of SARS-CoV-2. In community and healthcare settings, their use is intended as source control to limit transmission of the virus and personal protection to prevent infection. Population-wide masking has proven significant in reducing the transmission of COVID-19. Masks vary in efficacy, with N95 and surgical masks outperforming cloth masks, which are more common due to supply shortages, but even cloth masks, with their variability in fabric type and mask fit, provide wearers with substantial protection from particles carrying COVID-19. Among readily available fabrics, double-layered cotton, hybrid masks, and cotton flannel perform best and filtration effectiveness generally improves with thread count. Healthcare workers, given their exposure, are recommended against using cloth masks. Small-scale observational studies have shown evidence that masks reduce the community spread of COVID-19. More reliable, randomized controlled population trials are uncommon due to ethical and logistical issues. Clinical studies had not evaluated the efficacy of cloth masks in COVID-19 transmission by the end of 2021. The use of face masks or coverings in some cases has been recommended by American immunologist and NIAID director Anthony Fauci to reduce the risk of contagion. On 19 January 2022, the Biden Administration announced it would begin freely providing 400 million N95 masks in the United States. |
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In the COVID-19 pandemic, governments recommend the use of face masks with a main purpose for the general population: to avoid the contagion from infected people to others. Masks with exhalation valves are not recommended, because they expel the breath of the wearer outwards, and an infected wearer would transmit the viruses through the valve. A second purpose of the face masks is to protect each wearer from environments that can be infected, which can be achieved by many models of masks. Between the different types of face masks that have been recommended throughout the COVID-19 pandemic, with higher or lower effectivity, it is possible to include: cloth face masks; surgical masks medical masks; certified face-covering masks, considered respirators, with certifications such as N95 and N99, and FFP; filtering respirators with certifications such as N95 and N99, and FFP; other respirators, including elastomeric respirators, some of which may also be considered filtering masks. There are some other types of personal protective equipment PPE, as face shields and medical goggles, that are sometimes used in conjunction with face masks but are not recommended as a replacement. Other kinds of PPE include gloves, aprons, gowns, shoe covers and hair covers. There have been shortages of masks, which has led to the use of uncertified masks, with a worse performance. |
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Cloth face masks A cloth face mask is worn over the mouth and nose and made of common textiles such as cotton. Masks vary widely in effectiveness, depending on factors such as material, fit and seal, and number of layers. They are usually less effective at filtering than surgical masks and offer much less protection that filtering respirators. Unlike disposable masks, there are no required standards for cloth masks. One 2020 study found that a cloth mask was better than nothing, but not as good as a soft electret-filter surgical mask for protecting healthcare workers while simulating treatment of an artificially infected patient. Research on commonly available fabrics used in cloth masks found that cloth masks can provide significant protection against the transmission of particles in the aerosol size range, with enhanced performance across the nanoscale and microscale when masks utilize both mechanical and electrostatic-based filtration, but that leakage due to improper fit can degrade performance. A review of available research published in January 2021 concludes that cloth masks are not considered adequate to protect healthcare practitioners in a clinical setting. A 2013 study had volunteers wear masks they made themselves from cotton T-shirts, following the pattern of a standard tie behind the head surgical mask, and found the number of microscopic particles that leaked to the inside of the homemade masks was twice that of commercial masks. Wearing homemade masks also leaked a median average of three times as many microorganisms as commercial masks. But another 2020 study found that masks made of at least two layers of T-shirt fabric could be as protective against virus droplets as medical masks, and as breathable. |
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A woman sews a multi-layered woven cloth face mask on a sewing machine. Many people made cloth face masks at home during the pandemic. World Health Organization infographic on how to wear a non-medical fabric mask safely. A 2020 peer-reviewed summary of published literature on the filtration properties of cloth and cloth masks recommends two to four layers of plain-weave cotton or flannel, of at least 100 threads per inch. There is a trade-off in that increasing the number of layers increases the filtration of the material but decreases breathability. As of May 2020, there was no research on decontaminating and reusing cloth masks. The CDC recommends removing a mask by handling only the ear loops or ties, placing it directly in a washing machine, and immediately washing hands in soap and water for at least twenty seconds. Cold water is considered as effective as warm water for decontamination. The CDC also recommends washing hands before putting on the mask, and again immediately after touching it. There is no information on reusing an interlayer filter. Disposing of filters after a single use may be desirable. A narrative review of the literature on filtration properties of cloth and other household materials did not find support for the idea of using a filter. A layer of cloth, if tolerated, was suggested instead, or a PM2.5 filter, as a third layer. |
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A surgical mask is a loose-fitting, disposable mask that creates a physical barrier separating the mouth and nose of the wearer from potential contaminants in the immediate environment. If worn properly, a surgical mask is meant to help block large-particle droplets, splashes, sprays, or splatter that may contain viruses and bacteria, keeping them from reaching the wearer's mouth and nose. Surgical masks may also help reduce exposure of others to the wearer's saliva and respiratory secretions. Certified medical masks are made of non-woven material, and they are mostly multi-layer. Filters may be made of microfibers with an electrostatic charge; that is, the fibers are electrets. An electret filter increases the chances that smaller particles will veer and hit a fiber, rather than going straight through electrostatic capture. While there is some development work on making electret filtering materials that can be washed and reused, current commercially produced electret filters are ruined by many forms of disinfection, including washing with soap and water or alcohol, which destroys the electric charge. During the COVID-19 pandemic, public health authorities issued guidelines on how to save, disinfect and reuse electret-filter masks without damaging the filtration efficiency. Standard disposable surgical masks are not designed to be washed. Surgical masks may be labeled as surgical, isolation, dental, or medical procedure masks. The material surgical masks are made from is much poorer at filtering very small particles in range a tenth of a micrometer to a micrometer across than that of filtering respirators for example N95, FFP2 and the fit is much poorer. Surgical masks are made of a non-woven fabric created using a melt blowing process. Random control studies of respiratory infections like influenza find little difference in protection between surgical masks and respirators such as N95 or FFP masks. However, the filtering performance of correctly worn N95 FFP2 type filtering respirators is clearly superior to surgical and to cloth masks and for influenza, work by the UK Health and Safety executive found that live virus penetrated all surgical masks tested but properly fitted respirators reduced the viral dose by a factor of at least a hundred. Tsai Ing-wen, President of Taiwan, wearing a surgical mask Surgical masks made to different standards in different parts of the world have different ranges of particles which they filter. For example, the People's Republic of China regulates two types of such masks: single-use medical masks Chinese standard YY T 0969 and surgical masks YY 0469. The latter ones are required to filter bacteria-sized particles BFE 95% and some virus-sized particles PFE 30%, while the former ones are required to only filter bacteria-sized particles. |
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