Midnight in Chernobyl: The Untold Story of the World's Greatest Nuclear Disaster

by Adam Higginbotham

When one former nuclear submarine officer first took his seat at the desk in Chernobyl’s Unit One, he was horrified by the colossal size of the reactor and how antiquated the instrumentation was. “How can you possibly control this hulking piece of shit?” he asked. “And what is it doing in civilian use?”

Instead of engineering new safety systems, NIKIET simply revised the operating instructions for the RBMK-1000. After decades of accident-free operation of military reactors, the atomic chieftains of NIKIET and the Kurchatov Institute apparently believed that a well-written set of manuals would be enough to guarantee nuclear safety.

And under some circumstances—7 rods or fewer—pressing the AZ-5 button might not shut down the reactor at all, but instead trigger a runaway chain reaction. If this happened, the increase in reactor power following an AZ-5 trip might be so great that it would no longer be possible to halt the reaction before the entire reactor was destroyed.