Due to the characteristics of high-speed rail, such as speed, safety, intelligence, and economy, choosing to travel at high speed has become the norm. However, for passengers’ with cardiac pacemakers, the electromagnetic radiation from the pantograph–catenary arc has emerged as a significant public concern. In this work, the Schwarz arc model was adopted for the modelling of the pantograph–catenary arc, and the frequency domain analysis of the arc pulse was conducted. Based on the frequency domain characteristics of the arc, the electromagnetic exposure of the pantograph–catenary arc to the wearer of the dual-chamber pacemaker was evaluated. This assessment included the distribution of induced electromagnetic fields within the passengers’ pacemakers and cardiac tissue, and calculating of the induced voltage on the electrodes to determine potential health risks. In the simulation, two passengers were modelled, including one standing passenger and one seated passenger, and they were placed at two different positions within the train carriage for comparative analysis. The results indicated that the maximum induced electric field strength (Ein Max) within the passenger’s cardiac tissue was 1.297 mV m−1, and a maximum specific absorption rate (SAR Max) of 0.7065 nW kg−1. These values were within the basic restrictions for public electromagnetic exposure established by the International Commission on Non-Ionising Radiation Protection (ICNIRP). For the two passengers’, electromagnetic interference on the pacemakers was primarily concentrated on the metallic components, where the maximum magnetic field intensity (Hin Max) reached 3.235 × 10−4 A m−1. The induced voltages (Uin) on the electrodes for the passengers’ monopolar and bipolar sensing configurations were 0.068 mV and 0.00147 mV, respectively, both well below the sensitivity thresholds specified in ISO 14117:2019, which were 2 mV for monopolar and 0.3 mV for bipolar configurations. These findings suggested that the electromagnetic fields generated by the pantograph–catenary arc were well within the recognised acceptable limits for passengers with pacemakers.