Ambulance personnel in the North West say the HSE has made no effort to communicate with them to try to resolve an ongoing dispute over union membership.
Workers who are members of the Psychiatric Nurses Association are on picket lines across the region for a second day today.
Members are striking at Sligo and Letterkenny University Hospitals as well as at ambulance bases in Ballyshannon, Donegal Town, Dungloe, Killybeggs and Carndonagh.
They want the HSE to recognise the PNA, which has a specific branch for ambulance workers.
The HSE has so far refused, claiming that engaging with another union will harm good industrial relations.
Advanced Paramedic in Killybeggs and Secretary of the North West NASRA Branch, Christina Martin says they will continue to strike until the situation is resolved.