Ensuring reliability of electronic medical devices is becoming increasingly challenging. The number of incidents with devices intended for clinical usage associated with electromagnetic interference has been increasing over the years and this trend is expected to be maintained. Ensuring proper behaviour on a given device from an electromagnetic point of view can be very expensive given the equipment and facilities required to conduct standardised tests. However, this topic shall not be disregarded, as the smallest source of interference on a medical device can make the difference when a diagnosis is dependent on the readings of a device. This work exposes the issue related with EMI induced malfunction in medical devices and proposes a method for simple and affordable pre-assessment of electromagnetic susceptibility on a device for ECG acquisition. The setup created for this purpose is presented as well as the good practices that shall be taken into account for the development of the system. This is used to replicated two scenarios previously evaluated in an anechoic chamber. It is shown that it is possible to replicate certain conditions using this system leading to conclusions identical to those observed in the anechoic chamber.