First day back at Tustin Ranch Elementary School in California on 11 August Paul Bersebach/MediaNews Group/Orange County Register via Getty Images
AS THE nights begin to draw in and schoolchildren across the northern hemisphere start trooping back into the classroom, there are three words that ought to be inscribed on every blackboard: ventilation, ventilation, ventilation.
“Ventilation is a critically important control measure for covid-19,” says at the University of Leeds, UK, and a member of the UK government’s (SAGE).
Schools are a particular weak link in controlling the spread…
