Safety models: an analytical tool for risk analysis of medical device systems

Markov-chain models of software use have been used successfully to test software and to analyze the expected use of software systems. It is possible to augment a Markov-chain usage model of the expected use of a medical system, including hardware, software and human components, with information about the occurrence and mitigation of hazardous conditions. This augmented Markov-chain usage model, called a safety model, presents significant opportunities for the quantitative analysis of aspects of system safety.