Functional safety manager can’t assure that this product is safe. instead, he/she knows that it is not safe.

There is saying about interview. An interviewer cannot make a interviewee be hired but can make him/her failed to be hired. I believe that this is true and a similar correspondence can be possible in the functional safety project.

I review functional safety documents frequently, and functional safety scope is too vast for one person to know everything fully so I sometimes conduct incomplete review. Incomplete review means that even though I approve it, it cannot be ensured that it is fully achieved.

Because I understand my weakness, I tried to find nonconformances in the documents. At least I’m first auditor in this project. And if I don’t agree, then it cannot be proceed. In the near future, I have to respond against customer auditor’s questions. There should be some layers of reviewers like me. They act as if ‘safety-nets’ in the project, and they protect systematic faults in the project.

Final reviewer shall be customer side auditors(or assessors). In some ways, customer have to not only have a deep knowledge about product knowledge but also have a deep technical functional safety knowledge. If a person does not have both, team has to be arranged. And who does not have a deep knowledge about the project but has a functional safety knowledge has to enough review experience whether the product under review is well documented or not. And he has to help a customer side product champion to determine whether supplier’s safety concepts or their approaches are good to satisfy their safety requirements.

But…. even though they conduct such audit or assess, they cannot ensure that safety is fully achieved.

Safety Case Development

Now I’m focusing on developing safety case. I’ve interested in development a little bit, but I’m realizing that it is very important thing.

Safety Case is a logical argument that product is safe. To show that it is convincing, it has to be considered in the early stage of project.

Safety case is managed in the item based, it means that both OEM and supplier has to make their logical structure. In this sense, it is better for OEM to have a concept of structure of safety case and to guide supplier to achieve their supporting evidence.

Let’s assume that peoples are not qualified in the early stage of the functional safety project, but qualified evidences are produced in the last stage. Is it convincing that product is safe?

Anyway, I’m gathering papers, reports from automotive and avionics domain and it will take time to have a concept.


I guess consideration of Safety Case as your sword may possible.

Link: Power of your words