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The AZ-5 Button: How a Safety Test Destroyed Reactor Four
Audio is available on Spreaker — see link below.
At 1:23 AM on April 26, 1986, engineers running a routine safety test triggered a power surge that blew the roof off Reactor Four — and firefighters arrived within minutes, walking into invisible death. This is the night Chernobyl happened, reconstructed second by second.
Audio is available on Spreaker — see link below.
Before Chernobyl, Reactor Four was a point of pride. The RBMK reactor at the Chernobyl Nuclear Power Plant was Soviet engineering made real, a demonstration that the USSR had mastered atomic energy and done so safely.
The explosion wasn't an accident in the way most people imagine accidents. There was no sudden mechanical failure, no surprise malfunction from out of nowhere.
To run the test, operators needed to reduce the reactor's power output to between seven hundred and one thousand megawatts thermal. As they began lowering power, an operator made an error.
At one twenty-three and four seconds, the test began. The turbine generator was disconnected from the reactor, and the coast-down started.
The first alarms reached the Chernobyl fire station within minutes. Firefighters arrived at the plant before two in the morning.
Inside the plant, the response from management was shaped by two things. Genuine shock, and institutional denial.
Pripyat, the city built specifically to house Chernobyl workers and their families, sat three kilometers from the reactor. On the morning of April twenty-sixth, people woke up, sent their children to school, worked in their gardens.
The explosion had blown burning graphite across the plant site and ignited fires in multiple locations. Graphite, the material used to moderate the nuclear reaction in the RBMK design, burns at extreme temperatures and is extremely difficult to extinguish with water.
The health toll that would emerge over the following years wasn't immediately visible in April nineteen eighty-six. Eight point four million Soviet citizens were exposed to elevated radiation levels.
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