Effect of humidity on DC breakdown voltages in ambient air at high altitude

It is demonstrated that the IEC correction procedure is not adequate for direct-current voltage measurements at high altitude. This is mostly a consequence of the fact that the physical model employed, which is based on the field of propagation of streamers, fails to account for the combined effect of humidity and altitude. The experimental rod-plane results obtained by the authors are better modelled by an alternative semi-empirical model.