Mapping to IEC 61508 the hardware safety integrity of elements developed to ISO 26262

Abstract

Over the years, several functional safety standards for industries that handle safety electrical, electronic and electromechanical systems have been developed from IEC 61508 (generic). These include ISO 26262 (automotive), IEC 61511 (process), EN 50129 (railway), IEC 620621 (machinery), IEC 61513 (nuclear), etc. The emergence of these standards gives to the associated industries domain-specific identities. However, in certain cases, the rate of updating the standards is greatly overtaken by the rapid evolution of new technologies with a high potential to obsolete existing designs. Besides, IEC 61508-based critical components may experience shortage in the event of a global disaster as seen during the Covid-19 pandemic, hence the need for a robust substitution means. To address these problems, the concept of cross-domain reuse of resources is being promoted between industries that have unequal pace of alignment to the state-of-the-art. However, the framework for domain-to-domain (D2D) exchange must be clearly defined to avoid confusion. The objective of this paper is to investigate whether and how safety levels defined in ISO 26262 (automotive) can be mapped to safety levels in IEC 61508. The paper builds on review of literature and standards and is delimited to hardware elements