Anatoly Stepanovich Dyatlov (Анатолий Степанович Дятлов, Анатолій Степанович Дятлов; 3 March 1931 – 13 December 1995) was a Soviet engineer who was the deputy chief engineer for the Chernobyl Nuclear Power Plant.
Dyatlov was born in 1931 in Krasnoyarsk Krai, Russian SFSR, Soviet Union.
His parents were poor.
They lived near the Yenisei River and the penal settlements of Krasnoyarsk.
He ran away from home at the age of 14.
1959
He first studied in a vocational school, at the electrical engineering department of the Mining and Metallurgical Technical School in Norilsk, and worked three years as an electrician before he was admitted at the Moscow Engineering and Physics Institute where he graduated in 1959 with honors.
After graduation, he worked in a shipbuilding plant in Komsomolsk-on-Amur, in Lab 23 where reactors were installed into submarines.
During a nuclear accident there, Dyatlov received a radiation dose of 100 rem (1.0 Sv), a dose which typically causes mild radiation sickness, vomiting, diarrhea, fatigue and reduction in resistance to infections.
One of his two sons died of leukemia at age nine.
In his personal life, he loved poetry, particularly Pushkin's Eugene Onegin.
1973
In 1973, he moved to Pripyat, in the Ukrainian SSR, to work at the newly constructed Chernobyl Nuclear Power Plant.
His fourteen-year experience working on naval reactors in the Soviet Far East made Dyatlov one of the three most senior managers at the Chernobyl station.
He was in charge of Units Three and Four.
Dyatlov worked 6 or even 7 days a week for long shifts, while priding himself on his knowledge of reactor systems.
His management style was unforgiving, projecting an image of infallibility, and he often cursed at staff who did not follow his orders to the letter.
However, some workers say they respected him and the knowledge he held.
To those workers, he was seen as honest, responsible and a devoted man.
Other seemingly "lazy" workers, targeted by Dyatlov's high standards, saw him as tough, stubborn and unfair.
1986
He supervised the safety test, which resulted in the 1986 Chernobyl disaster, for which he served time in prison as he was blamed for not following the safety protocols.
On 26 April 1986, Dyatlov supervised a test at Reactor 4 of the nuclear plant, which resulted in the Chernobyl disaster.
In preparation, Dyatlov ordered the power to be reduced to 200 MW, which was lower than the 700 MW stipulated in the test plan.
The reactor then stalled unexpectedly during test preparations.
Raising power after this point put the reactor into a potentially dangerous state, due to xenon poisoning, as well as undocumented design flaws in the reactor, which were unknown to the operators at the time.
One major contributing factor to the accident was raising the power level after the reactor stalled at below 30 MW.
The operating manual was contradictory and lacked clear definitions, so the test program was allowed to continue.
"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. He said that the power decreased to 30 MW when switching between automatic rod control systems. This didn't mean any negative consequences. There are no units that haven't suffered from power losses. As well there are no operators that haven't allowed unscheduled power decreases for [one reason or another]. 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, the operators could only reach 200 MW due to xenon poisoning.
During the test, Akimov called for the AZ-5 scram button to be pressed to shut down the reactor.
A few seconds later, the reactor exploded.
After the explosion, Dyatlov ordered the control rods to be inserted by hand.
Too late, he attempted to revoke his order.
He called for increased water circulation to the reactor in an attempt to cool it, not knowing most of the systems had just been destroyed.
The reactor shop supervisor returned to the control room to say the reactor had been destroyed, but Dyatlov refused to believe him.
Dyatlov left the control room to evaluate the situation himself, even attempting to locate lost plant worker, Valery Khodemchuk.
He began to feel weak and started vomiting, caused by acute radiation syndrome, so gathered the operating logs from the control room and left for the administration building to report to Bryukhanov.
During the accident, Dyatlov was exposed to a radiation dose of 390 rem (3.9 Sv), which causes death in 50% of affected people after 30 days.
Ultimately, he survived.
He was admitted to Pripyat Hospital where he initially refused treatment, saying he just needed to sleep.
