For us in Oz, if overwater with single engine float equipped a/c, pax must have lifejackets and wear them, if over 30min at cruise speed or 100nm (whichever is less) from land, must have life raft, if you then require lift raft, a/c must have pyrotechnic signals, survial equipment & ELT.
But can't help you with regs in Ireland old chum.