Headteachers have questioned how much money the Department for Education will spend on improving ventilation in schools and how quickly this can be done to reduce the risk of Covid spreading.

School leaders have warned that a rollout of carbon-dioxide monitors to schools under a new £25 million DfE programme will only measure the problem of air quality, not solve it - and most schools are not likely to receive the devices before the end of next month.

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The department has said that the monitors will enable teachers to identify where ventilation needs improvement and “act quickly”.

Geoff Barton, general secretary of the Association of School and College Leaders, has asked “what happens next?” if ventilation problems are identified by the monitors once they are installed.

Covid: Will there be more money to improve ventilation in schools?

“We know that there’s more [guidance from the government] that is going to come out around these CO2 devices.  

“Special schools and PRUs [pupil referral units] are likely to get them early on. But for most schools or colleges, they are unlikely to get them until towards the end of October, and, frankly, the procurement hasn’t happened yet,” he told Tes.

“There is some misunderstanding around this. Some people are saying, ‘Great, this is the answer to the problem of ventilation.’ Of course, it’s not the answer. It simply gives you an indication of whether there is a ventilation issue.”

His thoughts were echoed by David Whitaker, director of learning at Wellspring Academy Trust in Yorkshire, who asked what funding the DfE would provide to ensure schools could resolve ventilation issues detected by the monitors.

“I think there are two sides to this - it’s a good thing that we’re investing in the potential to monitor carbon dioxide and, obviously, that shows the air quality in classrooms, but the big problem for me is what if that shows the air quality in classrooms isn’t good? What happens then?” Mr Whitaker told Tes.

“We do know that we have schools with quite crowded classrooms, we do know that we have schools with different types of ventilation systems.

“I know within our trust we’ve got schools where the windows don’t open, because they have quite modern ventilation systems.

“But what happens when the CO2 detectors say that the air quality isn’t good in a school and the only way that we can resolve it is buying new airflow systems or replacing windows?

“Who pays for the replacement windows and who pays for the new airflow systems? Is there any money from the DfE to back up the £25 million they’re spending on the CO2 detectors for any of the classrooms that aren’t adequately ventilated? So there are unanswered questions for me.”

Mr Whitaker added: “We know that what’s going to happen in the next couple of weeks - people will get boxes of CO2 monitors arriving in schools to be put up by caretakers and site managers, and that’s going to take hours and hours of work. So there’s a cost associated with that, with the time it takes to set them up.

“What’s the procedure if the monitor starts to indicate poor airflow?”

‘We should have been on the front foot’

Mr Barton has said the government should already have been on the front foot in terms of ensuring that classrooms were well ventilated.

“The evidence from Scotland, where they were able to get these into schools at the start of their term, showed that actually sometimes classrooms are excessively ventilated and that actually you don’t need the windows open as much as you thought you needed to,” he said.

“However, if you are in the sort of school that I used to run - we have 1930s buildings and in places you can’t open some of those windows - then the next stage is, if we are identified as a ventilation problem, what happens next?

“We really should have been on the front foot with this, like the American government was of actually doing an audit of classrooms and where there was repair work needed - taking paint off windows so the windows can open and all that kind of stuff. That should have been in place and we know that that will be the next stage.”

The DfE has been contacted for comment.

In a DfE statement announcing the provision of monitors, the department said: “More details will be available following the completion of procurement. However, all schools and colleges are expected to receive at least partial allocations during the autumn term, enabling all settings to monitor areas where they believe airflow may be weakest.

“As the monitors are rolled out, the department will provide guidance on their use.”