Does a hospital site constitute a hostile environment for microprocessor controlled equipment?

Equipment controlled by microprocessors has become widespread throughout hospitals. Even the simplest electrical equipment is likely to contain a processor to reduce cost and to increase flexibility. The number of occasions where equipment has malfunctioned and electromagnetic interference is suspected as a possible cause has increased. For example, it has been implicated in cases of uncontrolled infusion in equipment used for patient controlled analgesia systems. The authors investigate cases of suspected mains interference in hospitals, and survey the electricity supply in hospitals, assessing the quality of supply in `normal´ circumstances and measuring the severity of mains borne interference when present