Investigations into the Chernobyl Disaster

Lore & Background

The first official Soviet explanation was presented to member states at a review meeting held in Vienna on 25–29 August 1986. It placed the blame on the operators of the power plant, and the report that followed in September 1986 broadly supported that view. According to this account the accident resulted from gross violations of operating rules: the reactor was being run with key safety systems switched off, staff did not properly understand the technical procedures, and communication between safety officers and the operators running the test was insufficient.

On this reading the designers had considered such a combination of events impossible and so had not provided protection against it. Valery Legasov said in 1987 that disconnecting the safety systems was like airplane pilots experimenting with the engines in flight.

Reader's Guide

After the first report more information became available, and more powerful computing allowed forensic simulations. The revised report reflected that change, shifting the main weight from the operators to the reactor design.

Both reports agreed on one underlying factor: an inadequate safety culture at every managerial and operational level. The first report coined the term. The weakness was said to lie not only in operations but also in design, engineering, construction, manufacture and regulation.

Views about the causes were heavily lobbied by different groups, including the designers of the reactor, the personnel of the plant and the Soviet and Ukrainian governments, because the actual sequence of events and the plant parameters were uncertain.