An expert explains why scarves and masks with holes cut in them are less effective at preventing the transmission of coronavirus
Face masks have become a standard feature of everyday life, mandatory in most indoor settings. But despite being designed to completely cover the nose and mouth , it’s not uncommon to see them pulled to one side or resting on the chin – much to the annoyance of the general public. Here are some of the most popular versions – and expert opinion on why they don’t work.
The trapdoor
