Covid: Fresh air 'key to safer classrooms'

As children across England prepare to return to school, the focus is on testing, masks and the familiar routines of social distancing and hand washing.

But on top of all those measures, there's something that until recently hasn't had much attention: a good supply of fresh air.

Air matters because if someone is infected they'll release tiny virus particles called aerosols, which can accumulate and then be inhaled by others.

Computer simulations by engineers in Germany show how easily the air in a poorly ventilated room can become hazardous...

full article here.