MaizieD
there is some criticism of Wales for going ahead with the ozone based air cleaner. It has to be used in an empty room because ozone is toxic. Which seems to me to be a bit pointless because ideally you want the air to be cleaned while the children are in the room breathing in and out covid aerosols.
Units with HEPA filters which can be used when the room is occupied seem more practical.
CO2 monitors are fine up to a point but what is the school supposed to do if it shows a too high concentration? Whip all the children out until it goes down?
Exactly! It's better to filter the air in the first place. CO2 monitors are only a proxy to show that air isn't being circulated adequately. They do nothing to remove particles and don't indicate whether infection is present.
I have two HEPA filter devices, which I bought for my mother, who had COPD. Two would be enough for a classroom. I seem to remember they cost under £100 each. The filters are quite expensive, but the cost would be a drop in the ocean in the context of the amount which has been spent on Test and Trace.