A technical exam is being carried out at a construction site in the city centre after a builder fell from scaffolding yesterday afternoon.
The man in his 40's was knocked unconscious and suffered serious head injuries in the incident which happened on Trinity Street.
It's believed he was cutting a concrete slab in high winds at the time.
He was spotted by a member of the public who called an ambulance.
The HSA and Gardaí are both investigating.