The World Health Organisation has recommended wearing facemasks when indoors with other people, if the ventilation has been deemed inadequate, in an update to its Covid-19 guidance on masks, AFP reported.

The new recommendations apply in areas of known or suspected cluster or community transmission of the new coronavirus.

“WHO advises 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 new guidance says.

“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 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 facemask.