Opening windows between classes could be a good way of reducing the risk of virus spread in schools without letting rooms get “freezing cold”, an expert has said.
Professor Tim Sharpe, a member of the Environmental Modelling Group - a sub-group of the Scientific Advisory Group for Emergencies (Sage), which advises the government - said good ventilation did not require “opening all the windows all the time”.
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Professor Sharpe, from the University of Strathclyde, told BBC Breakfast: “It’s now well established that there is some risk of airborne transmission. It is difficult to quantify, but there is some risk so using ventilation is a really good way of mitigating that.
“It is one of a number of measures which you need to use in parallel, but making sure that spaces are well ventilated is a good way of reducing that risk, of helping to get fresh air in to get rid of the virus where it may occur.”
He added that there is a balance to be had between good ventilation and making sure people are not “freezing cold”.
He told BBC Breakfast: “It doesn’t mean opening all the windows all the time, it’s a managed process and obviously we’re balancing things. We want to get reasonable levels of ventilation, but we don’t want people to be freezing cold, so trying to sort of get that middle ground is something to aim for.
“As I say, it might be things like opening windows a little bit. It might be things like opening the windows a lot in between classes just to kind of flush things through a little bit. That could be a useful technique so that people aren’t cold or uncomfortable.”
He said air cleaners can work, but should be “an option of last resort” in rooms that cannot be ventilated in any other way.
And he added: “Some forms of air cleaner may be effective but you need to be cautious about which ones are being used. Some in themselves may be a little bit harmful, but there are good filtration systems, which may be helpful.”
Asked about air conditioning, he said: “Air conditioning is a slightly different thing, that’s primarily a sort of cooling thing. A lot of schools, bigger schools certainly, may have mechanical systems, so they are systems that use fans and ducts to move air around the spaces.
“And if those systems are working, as I said, they’re properly maintained, then they can give you good ventilation rates, and that can be properly managed.”
