From antagonisms to synergies: A systematic review of safety-security interrelations

As today’s critical infrastructures become increasingly digitalized and interconnected, the previously separated concepts of safety and security become increasingly intertwined. Researchers across domains thus call for joint consideration, e.g., in risk models and related standards. While this research field is emerging, the interrelations between safety and security are not yet well understood. However, a better understanding is highly relevant for anticipating, preventing, and handling incidents resulting from them. To shine light on these interrelations and their implications, we conducted a systematic literature review with a final data set of 213 publications. We not only systematized and quantified uncovered types of safety-security interrelations but also explored how different interrelations and related models impact on what is analyzed. From the systematization, we outline current trends and research gaps. Among others, we find a growing interest in safety-security interrelations as attested by sharp rise of publications and a growing diversification of models for co-analysis and co-engineering in the last years. The influence of security on safety is studied much more frequently as compared to an influence of safety aspects on security. Furthermore, we reveal an emphasis on studying the ”negative” types of interrelations, i.e., impairment and antagonism whereas potential synergies are scarcely analyzed. The findings can inform the more holistic development of truly combined as compared to previous sequential models for co-analysis and the design of processes and standards to support safety- and security-related stakeholders to anticipate and jointly cope with safety-security interrelations.