EMI levels at a "patient care location" in a hospital

Electromagnetic interference (EMI) has the potential to cause malfunctions of electronic based medical equipment including incubators, ventilators and pacemakers. The Canadian Standard Association (CSA) standard 232.2-M89 requires that the patient beds should be surrounded by a 1.5 metre "Patient Care Location" wherein only medical-grade electrical devices are permitted. Non-medical devices like TVs, VCRs, fans, etc are not allowed within this area because of electrical safety considerations. EMI levels from more than one medical-grade electrical device, operated simultaneously, may not be as low as anticipated. This is due to accumulative EMI levels especially in intensive care units and emergency rooms. In this work, EMI (field strength) levels are measured at various sensitive locations in the Health Science Centre, St. John's.