A Southampton school which was forced to shut for RAAC investigations has confirmed the prone-to-collapse concrete is not present in its buildings.
Mason Moor Primary School in Millbrook is now planning to bring forward its reopening.
The Helvellyn Road site was supposed to reopen next Monday - a week after the start of the new term - but now aims to welcome students back tomorrow.
In a letter sent to parents, headteacher, Daniel Constable-Phelps said he and the staff were relieved that RAAC was not present in the school.
However, he said he was disappointed with the backlash from parents received on social media.
Mr Constable-Phelps said: “I am disappointed to note some of the negative Facebook commentary that parents and carers have engaged in.
“This is an issue that is widespread throughout the UK. Closing a school will always be a last resort and was necessary so that I could be sure that children and staff were safe.
“You are right in your anger - the timing was unfortunate and it does have an impact on your children.
“However, making or engaging in hurtful comments about the school and members of the team will not be tolerated. This was a national issue and one we didn't know would affect our school until 31 August.”
Southampton City Council confirmed the presence of RAAC outside the main building of a school in Southampton.
The name of the school has not been confirmed but the council said no pupils have been impacted and the school has opened as normal.
A spokesperson from the council said: “Following surveys that have taken place this week, the council can now confirm that there have been no cases of RAAC identified in the school buildings which will impact pupils and staff.
"One school has been confirmed to have RAAC outside of their main building which has been isolated and cordoned off, and there is no impact on the education of the pupils. The school has opened as normal.”
RAAC is much less durable than ordinary concrete and only has a lifespan of around 30 years.
It was often used between the 1950s and 1990s as it is cheaper than standard concrete and quicker to produce.
The government has come under pressure to urgently address the issue after more than 100 schools in England were told to close buildings made with RAAC unless they put safety measures in place.
The announcement was made just days before the start of the new term.
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