Contractors were placed at risk from asbestos after a specialist surveying company failed to spot the potentially deadly material at two schools in Wales.
Contractors moved in to carry out refurbishment work on the Cardinal Newman Comprehensive School in Pontypridd, and Aberdare Boys School after both buildings were given the all clear by Normandie Analytical Services.
The company did plead guilty to two safety charges and was fined £18,000 and ordered to pay £21,000 costs by Llwynypia Magistrates Court.
HSE inspector Steve Lewis said: "This case demonstrates a repeated failure by this company to carry out systematic and comprehensive checks for asbestos.
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