Application of Software Reliability Model for Safety Assessment of E/E/PE Safety-Related Software

Quantitative and analytical safety assessment methods of E/E/PE safety-related software systems based on the SIL defined by IEC 61508 have been proposed. IEC 61508 does not provide us with quantitative and analytical methods for safety assessment of the software. Our methods give us quantitative information on safety measures for deciding the safety integrity level and testing time duration for achieving certain safety integrity level of E/E/PE software, respectively. Our stochastic modeling approaches are based on software reliability modeling and software reliability assessment techniques. Numerical examples for our methods have been shown for explaining how to use our software safety assessment approaches conforming IEC 61508.