Work at the site of the New Children’s Hospital in Dublin has resumed after an evacuation on Wednesday.
It is understood the evacuation was prompted by a fire but that the damage is not considered substantial.
In a statement, lead contractor BAM said no injuries were reported.
BAM said “a localised heat source activated” part of the sprinkler system on Wednesday, resulting in “water discharge”.
It added: “As a precaution and in line with standard procedures, the building was evacuated and emergency services attended.
“There were no injuries reported.
“The situation was quickly brought under control and is currently under review.”
Hundreds of workers from BAM and various other contractors are in the final stages of the multibillion-euro project.
A spokesman for BAM said “no impact to the overall project timeline is anticipated”.
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