Well, the short answer is that “everyone” in your organisation is responsible for the safety of the product. But in reality, it will typically be delegated to an individual from the Engineering team or the Safety, Quality or Reliability teams – if you’re lucky enough to have one of these.
Standards, such as ISO26262, IEC61508, ARP4761, MIL-STD-882E, ISO21434, and many others require you to perform numerous safety tasks – to prove that your design is safe. These tasks typically include HAZOP, HARA, SIL or ASIL, FMEA, FTA, reliability analysis, FMECA, FMEDA, FMES – to demonstrate that the design meets or exceeds your customer’s safety targets. These safety tasks require extensive documentation to evidence your analysis.
The biggest mistake we often see is that it is not until the product is reasonably well down the road of its design life cycle, maybe even at the prototype stage, before the safety flag is raised. Then there’s a mad rush to retro-fit the quality, reliability and safety analysis. Performing the various analyses in-house, or contracted out-to companies like Wilde-when there’s a shortage of in-house skills. Then the safety delegated individual has the daunting task of assembling all the analyses into a coherent System Safety Analysis or Safety Case.... Phew, job done, we managed to bring all these individual but related analyses together.
Then the inevitable happens,the dreaded design change. The client wants this ’n’ that changed– “it’s only minor”, they say. They will argue,till they’re blue in the face, that, “this was always our intended requirement – it’s NOT scope creep.” – hmmm!…. If you’ve never experienced this scenario before, then you’re very lucky – I’d suggest you go and buy a lottery ticket!
So, you agree to make the design changes – that wasn’t too painful was it? But wait, all of the safety analyses need to be updated now – changing the analysis figures, re-doing the workshops, updating the FMEAs and FTAs–all of the analyses. Then recompiling the Safety Case.
If this sounds all too familiar, then there’s 2 things you can do. First, start the safety analysis tasks earlier– obvious! Second, use a tool like Medini Analyze from Ansys– a single tool that guides you through the requirements of the Standard and conveniently incorporates all the analyses activities in one integrated environment – makes changes and updating a doddle!