The INMO has served notice of industrial action on Beaumont Hospital in Dublin.
In a statement this evening the union says 99 per cent of members voted in favour of industrial action over unsafe staffing levels in the medical and surgical departments.
A work to rule will begin on Wednesday December 16th.
There are currently 45 vacancies across the two departments and members says that is severely impinging on their ability to provide a safe level of care to patients.