The Kildare based Psychiatric Nurses Association plans to arrange more strike days, unless the HSE resolves an issue with some of its members.
500 ambulances workers belonging to the Sallins headquartered association walked off the this morning in a row over union recognition.
The HSE says it already recognises three unions for National Ambulance Service Staff, and feels engaging with another isn't in the interest of the public or workers.
It's also moved to reassure the public that it's ability to respond to emergencies is being maintained.
PNA Committee Secretary Tony Gregg explains why being able to choose their union is so important.