Plymouth Magistrates’ Court heard how three employees had developed and reported symptoms of HAVS but no action was taken.

The employees used tools such as rock drills and jack hammers for cliff stabilisation work which is often carried out by abseiling down a cliff and using the tools horizontally while working from ropes.

The affected persons began to experience symptoms such as pins and needles and aching hands, in one case since 2000. An occupational nurse was employed in 2016 and the HAVS problem was identified.

An HSE investigation found the risk assessment did not identify the actual exposure to vibration and had used out of date vibration data.

The investigation also found there was no health surveillance in place until 2016 and employees were not made aware of HAVS and its symptoms.

When symptoms were reported, the company had failed to take action.

Celtic Rock Services Limited of Devon pleaded guilty to safety breaches and was fined £36,667 and ordered to pay costs of £3,560.

Alwyn Griffith Hughes Thomas, director of the company also pleaded guilty and was given a 12 week custodial sentence, suspended for one year, a 12 week curfew and ordered to pay costs of £3,560.

Speaking after the hearing, HSE inspector Caroline Penwill said: “This was a case of the company and its director completely failing to grasp the importance of HAVS risk assessment and health surveillance.

“If they had understood why health surveillance was necessary, it would have ensured that it had the right systems in place to monitor workers health and the employees’ conditions would not have been allowed to develop, one of which was to a severe, life altering stage.”