Quantitative Assessment of the Diagnostics Effect on the Hardware Safety Integrity of the Safety-Related Electronic System Operating in Low Demand Mode of Operation

The paper deals with the quantitative assessment of the parameters influence of differently operating fault detection mechanisms on the hardware safety integrity of the safety function. It is considered that the safety function is implemented by an electronic safety-related system operating in low demand mode of operation. The quantitative assessment of the hardware safety integrity of the safety function is based on the use of homogeneous Markov chains. Proving the safety properties of the safety-related control system (proving, that the residual risk is acceptable) is a necessary condition for its implementation into an operation.