Asked by: Anonymous
In some nuclear reactors, water is used as a coolant. If this cooling mechanism fails, the temperature in the reactor core can rise dangerously high. The most dramatic such 'meltdown' was the Chernobyl disaster of 1986. Ironically, it began when engineers were testing aspects of the water-cooling system. A series of errors led to the unit overheating and destroying itself. The class of plant involved - called RBMK - is not used in the West.
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