A Method for Evaluating Electrical Safety of Medical Equipment and Installation

Abstract

Significant progress of medical engineering in recent years has introduced various kinds of electrical equipment into health and medical care. This situation inevitably involves a danger that medical equipment or installations may not properly be designed or used, thus produce electrical shock hazard. In order to circumvent such a hazardous situation, various schemes have been undertaken, but the author believes that it is necessary to develop an evaluation measure for the extent of safety secured by electromedical equipment and installations. This paper shows an evaluation method in terms of “Figure of protection”, “Multiplicity of protection” and “Protection sensitivity”, which are called “Three figures of merit for protection against electrical shock hazards”. Those figures are useful to (1) analyze a situation from the viewpoint of safety, and to (2) specify the items of testing in periodic inspection of equipment and installations. In addition to these, the figures will serve as guide to improving the equipment and installations by manufacturers, doctors, supporting staffs, hospital engineers and so forth.