[drob518]

I’m not sure why you think those are not a confluence of smaller events or that something outside the design spec isn’t one of those factors. By “small,” I don’t mean trivial. I mean an event that by itself wouldn’t necessarily result in disaster. Perhaps I should have said “smaller” rather than “small.” With the O-rings, the cold and the pressure to launch on that particular day all created the confluence. With Fukushima, the earthquake knocked out main power for primary cooling. That would have been manageable except then the backup generators got destroyed by the tsunami. It was not a case of just a big earthquake, whether outside or inside the design spec, making the reactor building fall down and then radiation being released.

[roenxi]

If Fukushima get hit by a disaster that is outside the design spec then the engineering root cause of the failure is established. There isn't some detailed process needed to figure out how a design should tolerate out-of-design events. And there isn't a confluence of smaller events, it is a very cut and dry situation (well, unstable and wet situation I suppose). There was one event that caused the failure. An event on a biblical scale that was hard to miss.

If you want Fukushima to tolerate things it wasn't designed to tolerate or fail in ways it wasn't designed to fail in then the swiss cheese model isn't going to be much help. You're going to need to convince politicians and corporate entities that their risk tolerance is too high. Which in a rational world would be a debate because it isn't obvious that the risk tolerances were inappropriate.

[namibj]

The design spect tsunami resistance is for getting away with just a couple days downtime plus what the grid concerns.

A much higher much rare case is what happened and which they didn't have a plan ready on hand.

Even if you treat the box as the special being they wre...