Anatoly Dyatlov

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Lore & Background

Dyatlov's management style was unforgiving, projecting an image of infallibility, and he often cursed at staff who did not follow his orders to the letter. Some workers respected him for his knowledge, seeing him as honest, responsible, and devoted; others saw him as tough, stubborn, and unfair. On 26 April 1986, he supervised a test at Reactor 4. In preparation, Dyatlov ordered the power reduced to 200 MW, lower than the 700 MW stipulated in the test plan. The reactor stalled unexpectedly during preparations. Raising power after this point put the reactor into a dangerous state due to xenon poisoning and undocumented design flaws. Dyatlov later recounted: 'I came up to them and saw the reactor power was at about 50–70 MW. I asked Sasha Akimov why the power had been so low... I allowed the further power increase and walked away from the panel.' During the test, the AZ-5 scram button was pressed, and seconds later the reactor exploded. After the explosion, Dyatlov ordered control rods inserted by hand, then tried to revoke the order. He called for increased water circulation, not knowing most systems were destroyed. When told the reactor was destroyed, he refused to believe it. He left the control room, began vomiting from acute radiation syndrome, gathered operating logs, and reported to plant director Bryukhanov. During the accident, Dyatlov was exposed to 650 rem (6.5 Sv), a dose that causes death in 50% of affected people after 30 days. He survived.

In Their Own Story

The control room hummed with tension as Dyatlov stood over the operators. The reactor had stalled at below 30 MW during test preparations. Dyatlov approached and saw power at 50–70 MW. He asked Akimov why it had been so low. Akimov explained the power decreased when switching between automatic rod control systems. Dyatlov later wrote: 'This didn't mean any negative consequences. There are no units that haven't suffered from power losses... Actually this [was] a trivial situation, so I didn't pay much attention to it. I allowed the further power increase and walked away from the panel.' While withdrawing a dangerous number of control rods, operators could only reach 200 MW due to xenon poisoning. Akimov called for the AZ-5 scram button. Seconds later, the reactor exploded. Dyatlov ordered control rods inserted by hand, then tried to revoke the order. He called for increased water circulation, unaware most systems were destroyed. The reactor shop supervisor returned to say the reactor was destroyed, but Dyatlov refused to believe him. He left the control room, began feeling weak and vomiting from acute radiation syndrome, gathered the operating logs, and left for the administration building to report to Bryukhanov.

Reader's Guide

Anatoly Dyatlov was the deputy chief engineer who supervised the safety test that caused the Chernobyl disaster. He was born in 1931 in Atamanovo, Krasnoyarsk Krai, to poor parents. He ran away from home at 14, studied at a vocational school and the electrical engineering department of the Mining and Metallurgical Technical School in Norilsk, worked three years as an electrician, then graduated with honors from the Moscow Engineering and Physics Institute in 1959. He worked in a shipbuilding plant in Komsomolsk-on-Amur, installing reactors into submarines. During a nuclear accident there, he received a radiation dose of 100 rem (1.0 Sv), which typically causes mild radiation sickness. One of his two sons died of leukemia at age nine, potentially due to radiation exposure. In his personal life, he enjoyed poetry, particularly Alexander Pushkin's Eugene Onegin, which he reportedly memorized by heart. After the Chernobyl disaster, Dyatlov was admitted to Pripyat Hospital, then transferred to Moscow Hospital 6. He was criminally charged with failure to follow safety regulations, along with Nikolai Fomin and Viktor Bryukhanov. At trial, only Dyatlov remained combative, saying operators were not responsible. He was given the maximum sentence of ten years. From prison, he wrote letters trying to explain RBMK reactor flaws and restore reputations. He was granted amnesty in late 1990 due to worsening health from radiation exposure. He wrote a paper published in Nuclear Engineering International in 1991 and a book claiming poor plant design was primarily responsible. He died of bone marrow cancer in Kyiv in 1995, almost certainly caused by his radiation poisoning from the accident.

Did You Know?

• Dyatlov ran away from home at age 14 and later graduated with honors from the Moscow Engineering and Physics Institute in 1959.
• Before Chernobyl, Dyatlov received a radiation dose of 100 rem (1.0 Sv) during a nuclear accident at a shipbuilding plant in Komsomolsk-on-Amur.
• One of Dyatlov's two sons died of leukemia at age nine, potentially due to radiation exposure.
• Dyatlov memorized Alexander Pushkin's Eugene Onegin by heart.
• During the Chernobyl disaster, Dyatlov was exposed to 650 rem (6.5 Sv), a dose that causes death in 50% of affected people after 30 days, yet he survived.