Ref. post 133. When I was employed by a company that supplied and repaired specialist I.T. equipment to various government organisations and agencies, the requirement for wiring mains plugs was same as you have mentioned. Before any item went out of the door, the mains plug was always examined on every item before shipment by a person other than the original fitter of it - just to make sure. That was necessary, since when the item arrived at the customer, the wiring to said plug would always be checked. If it was not to the stated requirement, the whole item would be returned - even if the mains cable was of the readily unplugable type!
Al.