A shutdown button made it worse
The Chernobyl disaster began during a late-night safety test. When a reactor became unstable, the operators pressed the emergency shutdown button. But due to a design flaw, the shutdown system briefly made the reactor more reactive—meaning the nuclear reaction sped up instead of slowing down.Chernobyl Reactor Design Flaw
The reactor was already on edge
Power had dropped far below the intended test level, many control rods had been withdrawn, and the reactor had become extremely unstable. In that state, boiling water created steam pockets that pushed the reaction even higher.Chernobyl Reactor Design Flaw
