Therac-25 Radiation Bugs Kill Patients

Between 1985 and 1987, the Therac-25 radiation therapy machine malfunctioned due to multiple software bugs. A race condition in the control code sometimes delivered radiation doses hundreds of times higher than intended, while the machine's safety interlocks had been removed in favor of software checks. The errors killed three patients and severely injured several others, making Therac-25 one of the most infamous cases of software failure in medical history.

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