TEEU stage pickets outside St James' Hospital
Pickets are being placed at Saint James' Hospital in Dublin in a dispute over management plans to remove key duties from electricians.
Members of the Technical, Engineering and Electrical Union are staging a four-hour work stoppage.
Union representatives say hospital bosses have ploughed ahead with the changes without engaging with them and they want meaningful talks to take place at the Labour Relations Commission.
Ian Mc Donnell of the TEEU said the group affected is relatively small, but it could pave the way for others to be "railroaded" unless the issue is addressed.