Abstract

A thorough account of the Therac-25 medical electron accelerator accidents reveals previously unknown details and suggests ways to reduce risk in the future. omputers are increasingly being introduced into safety-critical systems and, as a consequence, have been involved in accidents. Some of the most widely cited software-related accidents in safety-critical systems involved a computerized radiation therapy machine called the Therac-25. Between June 1985 and January 1987, six known accidents involved massive overdoses by the Therac-25-with resultant deaths and serious injuries. They have been described as the worst series of radiation accidents in the 35year history of medical acceler-

Citations

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