Production has been halted by Petrobras on its P-48 FPSO (floating production, storage and offloading) vessel after a fire earlier this week.
The company said in a statement the fire had been extinguished after an alarm was raised over the incident by union workers.
It is understood the first, which had started in Module 4 of the facility, began at around 1pm on Tuesday.
No immediate timeline has been given for when production will resume.
The FPSO is located in the in the Barracuda-Caratinga field in the Campos basin.