[blackdog]

The pressure vessels are part of the safety systems, but also become the problem once the reactor is overheated due to lack of cooling water/steam. The pressure vessels are really just steam bomb casings once a reactor superheats and any sort of cooling water is reintroduced.

What coolants do not expand under high temperature? (they would have to also be mighty plentiful)

[Drill Thrawl]

What coolants do not expand under high temperature? (they would have to also be mighty plentiful)

I wouldn't bother our local experts with that. Hillary Clinton is our country's expert on matters of nuclear coolant and shipping of same. And she is very relaxed now so don't worry.

/s