New developments in Safety Case preparation

This paper discusses some of the many challenges facing Safety Case authors. The varying (but largely common) requirements of the safety standards are compared with those of the intended readership of the Safety Case, and suggestions are made concerning the compilation and presentation of material. The contents of Safety Cases are defined in standards, and the work that underpins them is well understood, at least in principle. However, the various stakeholders have differing needs. For the developers, a complete repository of relevant information seems appropriate; the ISA, needs sufficient information, in adequate detail for them to be able to make a confident assessment of the safety of the subject system; whereas for the Safety Authority, a lower level of detail often appears appropriate. Where information is to be re-used, for example where a product is to be sold in different countries, or for different applications, a means of doing so efficiently - and potentially to the requirements of different standards - is needed. This paper discusses some of the challenges to Safety Case authors, and suggests how the information can be usefully managed and presented.