Hi Robin,
Although Irish wiring is similar to British in some respects, there are some significant differences between the regs.
Dave (djk) is in the Irish Republic and is familiar with them. I expect he'll be along soon and be able to comment......
Regarding no earths at the sockets, it sounds as though somebody might have "been at it." I assume you're talking about BS1363 sockets, not Shucko or old BS546 2-pin types?
I understand that TN-C-S (PME) is the normal earthing arrangement throughout the RoI.