EMP PROTECTION SYSTEM

An aspect of the disclosure provides a high frequency alternating current (HFAC) power distribution system configured to provide an HFAC power supply on an HFAC power supply bus to enable a plurality of electronic devices to be connected to the power supply bus for receiving HFAC electrical energy, the power distribution system comprising: an HFAC power supply configured to provide HFAC electrical energy to the HFAC power supply bus and having power supply output terminals for coupling to said bus; a protection circuit connected to the power supply and being arranged to provide a short circuit of the power supply; a power supply inhibitor operable to disable the power supply to prevent the provision of electrical energy; a detector circuit, configured to monitor gamma radiation to provide a detection signal; and a controller configured to operate the power supply inhibitor to prevent the provision of electrical energy in the event that the detection signal exceeds a threshold and then subsequently to operate the protection circuit to provide the short circuit.