Switching operations of disconnectors emit electromagnetic fields (EMF) to the external environment via gas-to-air bushing

posing a threat to the secondary equipment in gas-insulated substations (GIS) and potentially causing telecommunications outages in nearby residential areas. In this paper

a comprehensive method for EMF simulation is introduced. This method encompasses the entire process

from arc breakdown to very fast transient currents (VFTCs) and EMF generation

while considering radiation loss. A frequency-domain algorithm is proposed to address the complex

frequency-dependent problems encountered during simulation. The simulation of the 1000 kV Wuhu substation reveals that overlooking radiation losses leads to an overestimation of the high-frequency component of the EMF. The study further analyzes the EMF characteristics in relay protection rooms

control rooms

and residential areas under different operating conditions. Based on these EMF characteristics and in accordance with IEC 61000-4-10

this paper proposes immunity requirements for equipment located both within 1000 kV substations and in adjacent residential areas. This research makes a substantial contribution to assessing the transient electromagnetic environment caused by switching operations in GIS substations.