At 4:00 a.m. Wednesday, March 28, 1979, plant operators at the Three Mile Island facility set into motion the worst nuclear accident in U.S. history. And it all started with a minor malfunction exacerbated by human error.
Here’s how the Wikipedia entry on Three Mile Island accident describes the human error:
… such as human-computer interaction design oversights relating to ambiguous control room indicators in the power plant’s user interface. In particular, a hidden indicator light led to an operator manually overriding the automatic emergency cooling system of the reactor because the operator mistakenly believed that there was too much coolant water present in the reactor and causing the steam pressure release.”
Did you catch that? The operator misinterpreted the label of a warning light. Why? The curse of knowledge. [Read more…]