A lot of discussions on ISO 26262 jump straight to ASIL and safety goals.

But honestly, what makes those meaningful is the set of safety analyses behind them. And it’s not just one. Here’s the core:

🔧 FMEA (Failure Mode and Effects Analysis) + FTA (Fault Tree Analysis) → Identify what can go wrong (bottom-up + top-down)

📊 FMEDA (Failure Mode, Effects and Diagnostic Analysis) → Measure how well your safety mechanisms detect faults

🔗 DFA (Dependent Failure Analysis) → Check if your “independent” elements can actually fail together

🛡️ FFI (Freedom From Interference) → Ensure that one element (especially non-safety) cannot disturb another

💡 What matters in practice: These are not separate activities, they depend on each other.

If one is weak, your safety case is weak. If they’re aligned, your architecture becomes solid.

🔁 And if something new shows up? You go back and update the HARA. That’s where the real engineering work is.