I came across an electric DB placed atop a layer of 2 inch dia rebars which have been laid down in preparation of concreting. As a protection measure, an earth wire has been connected to the DB metal casing on one side and to the rebars on the other! 

Earth wires, as far as I know, should be connected to an earth rod which is to be driven by at least 60cm into the ground. However, when I asked the Elecrical Engineer (who is responsible for this practice) he was adament that this is a routine way of earthing DB's.

I asked him to remove it and follow the 'rod in the ground' method but would be grateful if someone can advise whether this is an approved earthing procedure.