Secondary staff and pupils will be expected to wear face masks when moving around schools in local lockdown zones, the government said tonight.
In another dramatic U-turn on its schools policy, as first revealed by Tes this afternoon, the Department for Education (DfE) has said face coverings "should be worn by adults and pupils" in communal areas in secondaries, such as corridors, in places "where the transmission of the virus is high".
And, while it is "not recommending face coverings are necessary" nationwide, the DfE said secondary schools will have the "discretion" to make masks mandatory in communal areas.
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This means, in most cases, it will be left up to heads to make the final decision on whether masks are required.
Up until now, the DfE had said face coverings in schools were "not recommended".
Schools should "not require staff, children and learners to wear face coverings", the existing guidance adds.
But the government has decided to revise its guidance in the wake of a new statement from the World Health Organisation (WHO) on when children should wear face masks, and after a similar U-turn in Scotland.
The WHO guidance states: "Children aged 12 and over should wear a mask under the same conditions as adults, in particular when they cannot guarantee at least a 1-metre distance from others and there is widespread transmission in the area."
The new DfE guidance, which is set to come into force from 1 September, will state that face coverings should be worn by secondary staff and pupils when moving around schools, such as in corridors and communal areas, in local lockdown zones.
But the department said face coverings would not be required in classrooms "where protective measures already mean the risks are lower, and where they can inhibit learning".
And the new rules will not apply to primary schools "where the risks to children are lower", the DfE said.
It added that, if the rate of transmission were to increase "across the whole country", it may be necessary to apply "stricter guidance" on the use of masks in schools nationwide.
"This is not necessary at the moment but the government will keep the evidence on transmission under constant review," the DfE said.
Education secretary Gavin Williamson said: "Our priority is to get children back to school safely. At each stage, we have listened to the latest medical and scientific advice. We have therefore decided to follow the World Health Organisation’s new advice.
"In local lockdown areas, children in Year 7 and above should wear face coverings in communal spaces.
"Outside of local lockdown areas, face coverings won’t be required in schools, though schools will have the flexibility to introduce measures if they believe it is right in their specific circumstances.
"I hope these steps will provide parents, pupils and teachers with further reassurance."
Geoff Barton, general secretary of the Association of School and College Leaders, said: "It was inevitable that the policy on face coverings would change following guidance from the World Health Organisation, and we recognise that the government in Westminster has responded to our call for a quick direction on this matter with the reopening of schools imminent.
"The new policy is discretionary, other than in places where coronavirus restrictions apply, and secondary school and college leaders will welcome the flexibility this affords them to decide what best suits their circumstances. We look forward to seeing the full guidance as early as possible."
The wording of the guidance is softer than in Scotland, where students in all secondaries will have to wear face coverings in school corridors and communal areas from Monday.
Scotland's new "obligatory" guidance on face coverings will also apply to pupils aged 5 and over travelling by bus, which Scottish education secretary John Swinney said took it further than recent advice from the WHO.