The Department of Transport will contact the owners of all vessels required to have a safety beacon to warn them of the possibility that the devices may be faulty.
Minister for Transport Leo Varadkar said the department would contact all registered owners of an emergency position indicating radio beacon (EPIRB) after an Australian manufacturer indicated there were 150,000 faulty beacons available internationally, 700 of them in Ireland.
He said a surveyor in his department became aware of a defective beacon while carrying out a survey on a passenger ship this year.
Two more defective units were found.
The manufacturer was contacted and the devices sent to Australia for testing, which showed defective microprocessors.
The department believed a safety alert should be issued and the manufacturer did so. Mr Varadkar said the department issued a marine notice about the alert. Ireland was the first country in the world to do so, he said.
Fine Gael TD John Deasy of Waterford highlighted the deaths of brothers Shane, Paul and Kenny Bolger last June, when their boat capsized in Tramore Bay.
He said that their emergency signal did not go off.
There are growing concerns that similar devices made by one particular manufacturer, GME, could be defective also .
The company had admitted that a microprocessor malfunction had been identified as the cause of a number of these beacons not working properly.
The department has begun an internal inquiry into the circumstances of reported identification of faulty emergency radio beacons three years ago. GME had issued a safety alert to owners of six models of the device made between 2005 and 2010. The company became aware of a microprocessor malfunction only after testing the beacon used by the three Bolger brothers.