Re: It could be worse
"One of the reasons Chernobyl went wrong so spectacularly is that it had a positive void coefficient"
And another one was that the operators had shut down virtually all of the safety mechanisms in order to perform an unauthorised experiment.
That's without even going into the non-nuclear stuff such as what happens when graphite sitting at 800C+ gets exposed to oxygen (Sellafield, Chernobyl), or several tons of molten Sodium gets dumped in a basement (Monju) or plain old water is heated up to 1100C or so (Fukushima)
It wasn't very long ago that most reactors required external energy to SCRAM because the control rods had to be lifted into position instead of being passively dropped into place. Even a balance beam would have negated that difficulty but apparently that was too hard for the designers to come up with.
Virtually every single safety device in industrial processes today exists because someone didn't think of what might happen if it didn't exist (or in some cases is now mandatory after beancounters decided it was too expensive). It's not helped by H&S inspections coming from within the industries in question and people not daring to think about the "what if" scenarios.
https://en.wikipedia.org/wiki/Flixborough_disaster was a wakeup call, but not enough of one.
Biting the hand that feeds IT
