The French science team finds Jin

The French science team including Danielle Rousseau are floating in an emergency raft at sea in the storm. In the distance they notice a man floating on a piece of debris and move towards him. They pull him into the raft and it is revealed that it is Jin.

Here's a translation of the dialogue of the team while on the raft.

How did Jin survive the explosion and what happened to him between the explosion and when the French team finds him?