The invention relates to an electric household appliance comprising a pump having a pumping chamber (11) including a movable wall formed by a diaphragm (12) made of an electrically conductive material comprising an inner surface covered with at least one layer (21) made of an electrically insulating material, and an outer surface, in contact with a piezoelectric actuator (13), characterized in that power is supplied to said piezoelectric actuator (13) by the voltage of a domestic power grid without inserting an insulation transformer therebetween, and in that said inner surface of the metal diaphragm (12) is covered by at least one first electrically insulating layer (21), having flame retardant properties, and by two additional electrically insulating layers (22, 23) of a lower thickness.