The stoppages will both begin at 9.00am
SIPTU members in Dublin Fire Brigade are to conduct two 24-hour work stoppages.
Workers will down tools on Saturday March, 18th and Monday March 27th.
They say this is to highlight their opposition to an attempt to remove ambulance call and dispatch functions from Dublin Fire Brigade.
The stoppages will both begin at 9.00am.
The announcement was made following a rally, which was attended by SIPTU Dublin firefighters and their supporters on Monday.
SIPTU sector organiser, Brendan O'Brien, said: "It is with deep regret that SIPTU members in Dublin Fire Brigade have been forced into conducting these work stoppages.
"This dispute results from our members' total commitment to providing the best emergency services possible to the residents of Dublin.
"These firefighters are withdrawing their labour to indicate, in the strongest manner open to them, their complete opposition to an attempt by senior management in Dublin City Council to break up the DFB Emergency Medical Service by removing its ambulance call and dispatch function.
"Removal of this function breaks a key link in the DFB Emergency Medical Service chain, which would result in a reduction in the effectiveness of the service, response time delays and expose the public to increased risk".
Firefighters voted by 93% to 7% in favour of strike action and 97% to 3% in favour of industrial action in February.