This study presents a hazard analysis method that uses a systems approach to analyse risks from Electromagnetic Interference (EMI) in complex systems. It builds upon the System-Theoretic Process Analysis (STPA) technique and extends it to EMI hazards by analysing the system control structure and the electromagnetic environment. A real-world case study with an insulin infusion pump illustrates the method’s effectiveness in uncovering EMI-related hazards. The method includes a traceability aspect represented as a directed acyclic graph, providing insight into hazards, con-sequences, and factors causing losses. By using this method, we can prioritize EMI scenarios and gain a better understanding of their system impacts, improving our awareness of EMI risks and enhancing decision-making for increased system safety.