A work-to-rule by 40,000 nurses over a claim for better pay and conditions is expected to begin this week.
The two unions involved, the Irish Nurses Organisation (INO) and the Psychiatric Nurses Association (PNA), began industrial action yesterday with a lunchtime protest at Cork University Hospital.
As well as further lunchtime protests, a work-to-rule is also planned in the early stages of the unions' campaign.
Details of what this would involve were outlined in documentation sent yesterday to branches of the INO and the PNA.
The unions told members that in the initial phase of any work-to-rule they should refuse to undertake clerical and administrative tasks such as answering telephones, ordering blood tests by computer, attending meetings with management at local and national level, filling forms, writing reports or assisting managers by opening and closing health centres.
The nurses have been told they should instead focus exclusively on caring for patients.
If the dispute is not resolved this week the work-to-rule is likely to be extended to more duties next week, by which time rolling work stoppages are also likely to begin.
No industrial action is expected today, but the unions have said they reserve the right to instruct members to take action at any time, giving minimum notice to employers. No such notice has yet been given.
The dispute, which could result in elective operations being cancelled if it escalates, is expected to be discussed at today's Cabinet meeting.
However, there were still no formal moves last night to try to negotiate with the nurses, who are seeking a 10 per cent pay rise, the introduction of a 35-hour week and a special allowance for nurses working in Dublin.
A spokesman for Minister for Health Mary Harney said the Labour Court recommended last November that nurses pursue their pay claim through benchmarking and it was still believed this was the way to go.
The unions say, however, that they have no confidence in benchmarking, and claim 14 other groups have had issues addressed outside it.
PNA general secretary Des Kavanagh said last night the guidelines on the work-to-rule would maximise the time nurses have available for patient care.
Liam Doran, general secretary of the INO, said many in political circles had acknowledged the nurses' claims were legitimate and something had to be done about them. However there had been no negotiations to date with management, which was disappointing.
Further lunchtime protests are planned for outside Galway's University College Hospital and the Mid Western Regional Hospital in Limerick on Friday.