Xeno426 wrote:Yes, the RBMK rector was designed by a human so it technically is human error.
Wasnt it because some uneducated engineer that try to push the reactor's limit overboard? Thats what i heard, i never read deep into it
I read a book on the whole thing written by an ex-Soviet nuclear engineer. One thing he noted was that other nuclear engineers knew the RBMK design was bad (the whole thing was designed by a thermal
engineer), but they couldn't get the thing replaced.
It happened during a regular test of the turbine system to make sure that, in the event of a drop in water pressure, there would still be enough pressure going through the turbines to provide power for emergency shut-down. It should
have been routine, but there were delays and the crew that was supposed to be performing the test--the experienced crew--clocked out and the next shift took over. A mostly green crew. For whatever reason, the auto-SCRAM system was shut off during the test and so was the safety system that prevented the rods from being removed as far as they were. Further, the control rods were graphite-tipped, meaning that when they are put into the reactor there is a spike in reactivity before the system is moderated. By the time anyone noticed something was wrong, the system was so far gone that introducing the control rods caused an immediate meltdown.
It was a comedy of human error, bad design, and a bad system. Accident reports were all need-to-know, so when there were other similar steam explosions at other plants the information on what went wrong was never disseminated to plants with similar systems; the pushed attitude of "nuclear power is completely safe" put people into such a complacent mood about it that safety was not properly observed; heading a nuclear plant was seen as a political feather in the hat, and so many of those at the very top of such plants (including Chernobyl) had no actual knowledge of nuclear physics or plant operation.