FFP2 and KN95 face masks offer extremely high levels of protection against infection with the coronavirus, according to new research underlining their relevance for everyday use in schools, shops, and other settings during the pandemic. Unlike cloth masks, masks with the European (FFP2) and US (KN95) filtering standards are known for their ability to also protect the person wearing them. However, the level of protection depends entirely on how well they fit the wearer, as researchers from the Max Planck Institute for Dynamics and Self-Organisation in the German city of Goettingen report in a st...