A shock prevention device for an electrical distribution board having at least one incoming terminal and one or more bus conductors for distributing electrical power from the incoming terminal to a plurality of outgoing conductor terminals projecting from a housing of the distribution board, the shock prevention device comprising an insulating body adapted to receive and shroud at least one conductor terminal; a moveable element moveable relative to the body so as to place the device in one of a first configuration in which the device can be fitted to or removed from the distribution board so as to cover the exposed terminal and a second configuration in which the device is braced between the conductor terminal and part of the distribution board housing, whereby removal of the device is prevented; and means for locking the moveable element in the second configuration.