A structured approach to selecting and justifying software safety evidence

The safety assurance of software is ultimately demonstrated by the evidence that is put forward. There is a range of existing guidance on the types of evidence that may be used to demonstrate the safety of software, however questions remain as to the sufficiency of the evidence suggested by such guidance. We propose that the only way to determine the sufficiency of the evidence is to consider its capability to address specific explicit safety assurance claims in a software safety argument. In this paper we propose a lightweight approach to selecting and assessing software safety evidence.