The World Health Organization recommended wearing face masks when indoors with other people, if the ventilation has been deemed inadequate. In its beefed-up guidance, WHO advised that the general public should wear a non-medical mask in indoor (eg shops, shared workplaces, schools) or outdoor settings where physical distancing of at least one metre cannot be maintained. The WHO also recommended wearing masks if a visitor outside your household came to your home.
“If indoors, unless ventilation has been assessed to be adequate, WHO advises that the general public should wear a non-medical mask, regardless of whether physical distancing of at least one metre can be maintained,” the new guidance said according to reuters.
The UN health agency also urged people not to wear masks during vigorous physical activity, and not to use masks with valves, saying they bypassed the filtration function of the face mask.
In its fourth update on mask guidance during the pandemic — the last was in August — the WHO called for wider use in health-care settings, especially in areas plagued by infection clusters or community transmission.
Health workers could wear N95 masks if available when caring for COVID-19 patients, but the only proven protection is when they are doing aerosol-generating procedures, the WHO said.
The organization said however that if masks were not available, or if people had difficulty wearing a non-medical mask — for example people with cognitive, respiratory or hearing impairments — then face shields may be considered as an alternative.
“If face shields are to be used, ensure proper design to cover the sides of the face and below the chin,” the guidance said.