Believe it or not, one of the world's worst disasters was caused by none other than a safety test. Well, a safety test and Soviet secrets, but mainly a safety test. A test to determine if under attack or a black-out, that the turbines used to keep the reactor cool would have enough inertia to bridge the 70 second gap that the back-up diesel-powered generators needed to get up to full speed and keep coolant pumping through the core.
There are a few factors that stacked against the plant operator's favour that night, but the biggest would be a lack of information. We’ll pick this up later, but a tiny button called “AZ-5” was the trigger behind the bullet.
The test was long overdue, promotions were on the line and Deputy Chief Engineer – Anatoly Dyatlov was not going to let another failed test go against his career. Under the control of Viktor Bryukhanov and Nikolai Fomin, the test began. However, the conditions of the reactor were not optimal for it to produce any valuable data. The power was too low and the reactor was in a ”xenon pit”, but the test went ahead anyway. What happened next changed the world and unleashed a disaster that would cost the Soviet Union around $230 billion and worse, the deaths of thousands of people.
The official Soviet death toll? 30.