Lancashire County Council says there are "no safety concerns at this time" that any of its schools might be affected by concrete prone to collapse.
But the council said it was carrying out inspections on a "small number of older schools" as a precaution and expected to conclude these later this week.
Fears over dangerous buildings began after the government announced on Thursday that around 104 schools or "settings" in England found with concrete prone to collapse were set to be closed or disrupted - on top of 52 that have already been affected this year.
The full list of schools affected has not been published but is expected to be released soon.
The type of concrete forcing the closures is Reinforced Autoclaved Aerated Concrete, known as RAAC.
It was used to build roofs, schools, colleges and other buildings from the 1950s until the mid-1990s, according to GOV.UK.
In comparison to traditional concrete, RAAC is weaker. It is made in factories using fine aggregate, with chemicals to create gas bubbles and heat
A Lancashire County Council spokesperson said: "There are no safety concerns at this time relating to presence of reinforced autoclaved aerated concrete (RAAC) in the 303 maintained schools the county council is responsible for.
"As a precautionary measure, we are carrying out detailed surveys on a small number of older schools that have had extensions and aim to have these concluded by the end of this week.
"This is in addition to visual surveys carried out by us earlier this year at a number of maintained schools where a possible presence RAAC was identified.
"The Department for Education (DfE) is leading on the national investigation and is liaising directly with schools where a Diocese or Multi Academy Trust is the responsible body.
"We were made aware over the weekend that the Lancaster Diocese has instructed Our Lady’s Catholic High School in Fulwood to close for two days pending further investigation.
“The presence of RAAC has been identified in some areas of the school. While we are not the responsible body for the school, we will work with the Diocese should they require support with this matter.
“We have also been made aware that Fulwood Academy has closed for two days to allow it to undertake a new survey of the building, although no RAAC has yet to be identified and we understand the closure is precautionary.
"Parents will be contacted by their school if their school is impacted by this issue."
Labour is calling on ministers to "come clean" and publish the full list of schools that will be impacted, as they have not yet been officially named.
Schools minister Nick Gibb said the government intended to do that "in due course" but he wanted parents to be informed by the school before they read about it in the media.
He also suggested more schools could be affected as not all building surveys have been completed.
Mr Gibb said in most cases "just a few buildings" or rooms within the affected schools will have to shut but "in some cases it will be the whole school".
Concerns about RAAC - a lightweight concrete used up until the mid-1990s - in public buildings were raised in 2018, prompting accusations that ministers have failed to act quickly enough.
In 2022, the Office of Government Property sent a safety briefing notice to all property leaders, saying that "RAAC is now life-expired and liable to collapse".
Mr Gibb said "new evidence" over the safety of RAAC emerged over the summer which prompted the government to change its guidance.
Experts have warned the risks may extend beyond schools to hospitals, court buildings and prisons, where the material is present.


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