Do we need conduit covering on our electricity cables?

[goldiecliff]

We have had some extra sockets installed. Unfortunately neither of us was able to be at home today and the electricians were left to it. They have installed all the extra sockets and now the gaps around the sockets need plastering. However they have not put the cables that run to the sockets in conduit covering and I am wondering if we are OK to just plaster over the top or do they need covering. The only cable that is exposed is approximately 2 inches between the top of the skirting board and the bottom of the sockets (the cabling runs under the floorboards to an existing socket). Thanks for any help.