A council education department has asked for £100,000 to re-check schools for asbestos because it fears previous surveys – completed up to 20 years ago – are inaccurate.

The request came after a pupil kicked a hole in the wall of a school building, exposing asbestos.

It set off “alarm bells” that previous asbestos surveys could be inaccurate because it hadn’t been identified in earlier investigations.

The incident was revealed in a capital business case submitted by Conwy county council’s education department and seen by its cabinet this week.

It has led to an application for £100,000 in capital funding to pay for a further asbestos survey, to check nothing else was missed in previous investigations.

The discovery has left the authority desperate to check that no more than the 59 schools it has identified as having asbestos contain the material.

The report said: “This incident has raised alarm bells regarding the accuracy of our current asbestos survey results.

“The asbestos surveys the authority is reliant upon as part of its asbestos management obligations were undertaken as far back as 20 years ago, and the fact that this particular item was not even classed as suspected asbestos casts doubt on the veracity of the surveys.

“Many of the asbestos registers show numerous items of ‘presumed asbestos’.

“In many cases, the item in question is not asbestos and an enhanced survey would enable the authority to reduce the number of items identified as ‘presumed asbestos’ and allow it to concentrate its efforts on those items that genuinely do consist of asbestos.”

Exposure to the material over prolonged periods can lead to serious health issues such as mesothelioma (a type of cancer that affects the lining of the lungs and digestive tract), lung cancer, asbestosis (scarring of the lungs) and thickening of the lung’s lining (pleural thickening).

It was banned in 1999 but can be found in many public buildings, including schools, which were built or refurbished up to that date.

The uses for asbestos in the county’s schools range from “insulation materials associated with the school’s heating system, to floor and ceiling tiles and wall panels”, according to the business case.

The study explained how it was believed asbestos particles were only released into the air if panels were damaged or broken.

However it claimed recent evidence suggested “the mere presence of asbestos in a building means those fibres may be released into the air even if the asbestos is not physically damaged or disturbed”.

In 2013 the Committee on Carcinogenicity (CoC) confirmed children are more at risk from asbestos than adults as they will live longer, providing greater opportunity for any asbestos disease to develop.

The younger a person is, the higher the threat of disease, with the lifetime risk of developing mesothelioma for a five-year-old said to be around five times greater than for a 30-year-old.

Some of the material is situated in children’s classrooms and the council’s policy had been “identification, management and inspection” of it.

The report said the £100,000 for the study would allow Conwy county council to “plan for the phased removal of asbestos from its schools”.