Computational comparison of charge neutralisations of conductors and insulators with corona ionisers

► Conductor and insulator charge neutralisations are compared using a 2D EHD model. ► The validity of the standard test relying on a conductive plate is discussed. ► Ion behaviour in early-phase insulator neutralisation is different from conductor one. ► We demonstrate that ionisers themselves can cause a hazardous situation. ► Proper usage of ionisers and the standard test is proposed.