EMI problems for medical devices

Diagnostic and clinical equipment is required for accurate measurement of patients, health monitoring and control. Hence, a modern hospital is always updating its diagnostic equipment from time to time as the technology advances. The new facilities are being installed in the existing places without ascertaining the possible EMI problems. The problem is acute, with ever increasing wireless communication networks in the form of cellullar phones, police networks and private communication networks where the EMI generated may cause the medical devices to malfunction or to indicate false readings. The European Union has drafted the requirements as a medical directive for equipment which is used for clinical and non-clinical purposes. The same requirement will be imposed on all equipment manufacturers and the users to safeguard the use of medical devices. In this paper the authors bring out the typical EMI sources encountered by the types of medical devices indicated above and possible prevention through testing of devices as per IEC/EN standards.