It seems to be a combination of poor design and not following operational procedures to manage the poor design. https://world-nuclear.org/information-library/s

It seems to be a combination of poor design and not following operational procedures to manage the poor design. https://world-nuclear.org/information-library/safety-and-security/safety-of-plants/appendices/chernobyl-accident-appendix-1-sequence-of-events.aspx https://world-nuclear.org/information-library/safety-and-sec...