500 ambulance personnel are striking today, in a dispute with the HSE over union recognition.
The crew members, who are part of the Psychiatric Nurses Association, will picket outside ambulance bases in Dublin, Cork, and other locations between 7am and 5pm.
The National Ambulance Service says it has detailed contingency plans in place.
That includes having Defence Forces paramedics on standby, managers carrying out frontline duties, and confirmation that personnel from other unions will be working as normal.
Peter Hughes, General Secretary of the PNA, says contingency plans are in place to deal with emergencies during today's strike action.
"From 7am to 5pm our members will be on strike," he said.
"We will cover emergencies, so emergency cover will be provided. Non-emergency will not be provided."
