A corona discharge gas ionization apparatus for delivering an ionized gas stream to a charge neutralization target, the apparatus receiving a non-ionized gas stream that defines a downstream direction and comprising: at least one through-channel for receiving the non-ionized gas stream and for delivering the ionized gas stream to the target; a non-conductive shell disposed within the through-channel and having an orifice disposed at one end thereof; at least one corona discharge ionizing electrode for producing charge carriers (10;11;11') within the nonconductive shell in response to the provision of an ionizing signal having a cycle T with positive and negative portions, wherein the charge carriers comprise clouds of electrons, positive ions and negative ions that enter the non-ionized gas stream through the shell orifice to form the ionized gas stream; a power supply for providing the ionizing signal to the ionizing electrode, wherein the negative charge carriers are produced by the ionizing electrode during a time Tnc of the negative portion of the ionizing signal; at least one non-ionizing reference electrode that is electrically insulated from the ionized gas stream and positioned downstream of the ionizing electrode, the reference electrode producing a monitor signal responsive to the charge carriers (10; 11; 11') within the ionized gas stream, wherein the charge carriers produced by the ionizing electrode oscillate between the ionizing electrode and the reference electrode; and a control system communicatively coupled to the power supply and to the reference electrode to control the ionizing signal provided to the ionizing electrode, at least in part, responsive to the monitor signal to define a corona discharge threshold. at least one through-channel for receiving the non-ionized gas stream and for delivering the ionized gas stream to the target; a non-conductive shell disposed within the through-channel and having an orifice disposed at one end thereof; at least one corona discharge ionizing electrode for producing charge carriers (10;11;11') within the nonconductive shell in response to the provision of an ionizing signal having a cycle T with positive and negative portions, wherein the charge carriers comprise clouds of electrons, positive ions and negative ions that enter the non-ionized gas stream through the shell orifice to form the ionized gas stream; a power supply for providing the ionizing signal to the ionizing electrode, wherein the negative charge carriers are produced by the ionizing electrode during a time Tnc of the negative portion of the ionizing signal; at least one non-ionizing reference electrode that is electrically insulated from the ionized gas stream and positioned downstream of the ionizing electrode, the reference electrode producing a monitor signal responsive to the charge carriers (10; 11; 11') within the ionized gas stream, wherein the charge carriers produced by the ionizing electrode oscillate between the ionizing electrode and the reference electrode; and a control system communicatively coupled to the power supply and to the reference electrode to control the ionizing signal provided to the ionizing electrode, at least in part, responsive to the monitor signal to define a corona discharge threshold.