The MISRA “Guidelines for automotive safety arguments” provide clarity on how to develop safety arguments in line with existing standards, with a view to justifying that the risk associated with an automotive system is within industry norms. Types of evidence to support the argument are also suggested, as well as advice on practical application.
Though absolute safety, the absence of all risk, is an infeasible target, particularly for complex road vehicle systems involving embedded electronics and close interaction with human users, conformity with safety and quality standards and guidelines is necessary.
Engineers have an obligation to investigate and communicate the level of risk associated with their systems and services, and are expected to produce and explain the evidence for the safe design and use of these systems. A key part of this is explicitly justifying why the available evidence is sufficient and trustworthy.
The concept of Safety Cases has been widely adopted across the automotive industry and beyond. Most definitions of Safety Cases are centred on two concepts: evidence and argument. Current safety standards are, in general, good at providing detailed guidance on the different types of evidence that are recommended for meeting the compliance and safety requirements. However, there has been a lack of practical guidance on how safety arguments are developed, reviewed and maintained for automotive applications.
These guidelines provide a more holistic framework through which to develop safety arguments, with practical guidance and examples.
The concepts are applicable to safety standards used in all industries and are illustrated by detailed application to ISO 26262:2018.