Good Samaritan Bill 2005 being discussed in the Dáil.
Didn't read through it, but I was told when I was being trained in the AED that the principle applied in Ireland.
It's happened once in England - a man fell from a bike in one of those motorcycle scramble things, and was dragged out of the way by the St John crew. He was paralysed because of it, and sued St John in England, but the judge ruled that if he'd been left, there was a bike about to land on him and do a lot worse than paralyse him. Got thrown out of court, essentially, for being an ungrateful ****. English law usually acts as the starting point here, although it hasn't been tested as far as I know.