Almost half of teachers questioned by a union do not think it is safe for pupils to return from tomorrow as planned.
The NASUWT union questioned 780 teachers in Scotland ahead of schools reopening this week.
The survey found teachers are anxious about going back to work and have not been given enough information or time to prepare.
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Some 45 per cent of those questioned do not think it will be safe for pupils to return, with 42 per cent uncertain.
The majority (67 per cent) do not feel prepared to go back to their school or college and 87 per cent feel anxious about returning when it is reopened to all pupils.
More than 70 per cent in the survey, which was conducted between 5 and 9 August, had not been given assurances by their schools that PPE would be provided.
NASUWT general secretary Dr Patrick Roach said: “Teachers need to be given the same level of protection as employees in any other workplaces.
“Our survey has highlighted that teachers have not been given assurances that even basic hygiene measures to help suppress the virus, such as paper towels and soap and hot water, will be made available to them. This is deeply concerning and must be addressed immediately.
“We have also heard from many cases, teachers who have not been told about the safety measures that will be in place to help prevent virus spread.”
He added: “The Scottish government and school employers have a duty to listen to and address teachers’ safety concerns and take urgent action to ensure that schools reopen safely this term.”
Jane Peckham, NASUWT national official for Scotland, said: “The fact that almost half of teachers have told us they don’t feel their school will be a safe environment for pupils to return to should be a major cause for concern.”
A Scottish government spokesperson said: “We agree that the health and wellbeing of pupils, students and staff should be the top priority when it comes to reopening schools and colleges.
“The guidance on preparing for the start of the new school term sets out the approach that must be taken, including a number of health mitigations. They include risk assessments, enhanced hygiene measures and Test and Protect.”
The spokesperson added: “A surveillance programme is being developed for schools, where regular testing and survey data will identify symptoms and infections in the school population.
“This will allow regular reporting on incidences of infection and inform the ongoing development of guidance for schools.”
Meanwhile, tougher measures could be taken against schools in the North East of Scotland if control of community coronavirus transmission is lost, according to Scotland’s national clinical director.
Jason Leitch was speaking to BBC Radio Scotland this morning when he urged parents to be “cautious” but not “overly worried” about the return of pupils to class, which is to begin across the country from tomorrow.
However, he said schools will be in the “equation” if tougher measures are necessary to control the outbreak in Aberdeen.
The number of cases in the Covid-19 cluster in the city stood at 134 on Sunday, with a total of 728 close contacts identified.
Mr Leitch told the Good Morning Scotland programme: “It’s not the number of positives in [the NHS Grampian area], it’s a matter of community transmission.
“If we, the country, lost control of that outbreak and we couldn’t trace a large number of cases back to the original cases from last weekend, that’s when we would start thinking about doing things.
“You’ve seen us already take action last week – about travel, about indoor meeting up, about hospitality – and we won’t hesitate to do that in other parts of the country or to take stronger measures in Grampian and Aberdeen if that’s what’s necessary.
“Schools will have to be in that equation, of course they will.”
Mr Leitch said his advice is that it is safe for teachers to return, but that they should familiarise themselves with the relevant guidance.