Abstract: An electrical safety apparatus arranged to be connected between an electrical power source and a load to provide protection against electric shock due to, for example, the insertion of probes or needles into a potentially live socket by a child, and against shock form exposed conductors (e.g. the severed cable of an electrical appliance) connected to the power source. When the apparatus is connected to an electrical power source and then connected to a load, the apparatus first applies a low test voltage or test current to determine that the impedance of the load is within a safe range which excludes that of the human body, before connecting the load to the normal electrical power supply or mains. After the apparatus has been connected to a load of suitable impedance the apparatus monitors the power drawn by the load so that should the impedance of the load change to an unsafe value during operation of an electrical appliance (e.g.