*THE CAUSE*


[ARROW] Safety System Inadequacies
"The most important weakness was in shutting the reactor down. At Chernobyl, the shutdown rods are part of the normal plant control system rather than being a separate emergency system." [37]

Result of inadequacy
a fault in the control system also makes the emergency shutdown unable to function.
the emergency shutdown desired effect relied on the reactor being operated correctly.
there had to be at least 30 control rods in the core for the emergency shutdown to work to according to standard .
the reactor could not be run at low power normally.
"Pulling the rods all the way out not only slowed down the emergency shutdown, but caused the power to increase when they first started going in." [38]

In the accident, these requirements were disregarded by the operator and thus the emergency shutdown was slowed down noticeably.


"The second weakness is that Chernobyl had only partial containment. " [39]

Diagram-6 No upper containment at the Chernobyl Reactor No. 4
[No upper containment at the Chernobyl Reactor No. 4]

Result of inadequacy
the partial containment was bypassed and went out the top of the reactor core where there were no leak-tight boxes.
the hot fuel and graphite were exposed to air because of no containment on the top of the reactors.

If the containment were complete, the water and steam from the broken pipes would have made the atmosphere of the building similar to a rain forest when experiencing a tropical storm. Therefore, the water would have dissolved almost all the cesium and radioactive iodine that was freed. The cesium and iodine would not get out even if the containment leaked. This chemical reaction did not occur at Chernobyl because the hot fuel and graph ite were exposed to air as mentioned above.



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