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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 both community and healthcare settings, their use is intended as source control to limit transmission of the virus and personal protection to prevent infection. Their function for source control is emphasized in community settings. 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 to each wearer from environments that can be infected, which can be achieved by many models of masks. In public health, social distancing, also called physical distancing, is a set of non-pharmaceutical interventions or measures intended to prevent the spread of a contagious disease by maintaining a physical distance between people and reducing the number of times people come into close contact with each other. It usually involves keeping a certain distance from others (the distance specified differs from country to country and can change with time) and avoiding gathering together in large groups.