Normally system and sub system level functional requirements will be "what" the system should do not "how" or "implementation. When it comes to Functional Safety, is FSR and TSR written in "what" vehicle or System should do when failure occurs or is it "how"
In general requirements are more “what” must be done or implemented, not so much “how” to do or implement it. But of cause is a TSR already the “how” to implement a FSR. That kind of relationship applies to any hierarchical levels of requirements. We hope this helps you further!
As a supplier I have noticed that the fsc is never given by the OEM. Usually just vague "safety requirements" without any supporting info or rational. When I request item definitions and fsc's you usually get vague answers like "its protected by ip". For the safety of the complete system I think its critical that work products from the concept phase is given as input to the development at the system level phase. Comments?
Yes, it is normal that the OEM does not provide the FSC. It is his responsibility. And yes, the OEM must then provide (good!) functional safety requirements with ASILs allocated. The supplier does not need to know the full FSC and should however know for which item(s) his development is. And that is normally the case. We hope this helps you further!
@@KUGLERMAAGCIE Thanks for the answer. As part of the safety culture I usually insist on understanding the FSC, especially when FSR's are badly written or incomplete. Just saying "it's the OEM's responsibility" is not ok if you suspect incompleteness or incorrectness in upstream work products.
