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Video Transcript: Chernobyl Accident Examined

[Time Stamp: 00:13] The following comments on the Soviet report on the accident are from a Japanese national television report.

[Time Stamp: 00:21] A Russian report said that the accident was caused by violations of operational procedures.

[Time Stamp: 00:28] But let's examine that and see if it really was due to an operator's error.

[Time Stamp: 00:33] The first violation: April 25th 1400 hours: The bypassing of the emergency core cooling system.

[Time Stamp: 00:42] Before the experiment, if the ECCS is not bypassed, the reactor will shutdown and the experiment cannot be run.

[Time Stamp: 00:53] In order to continue the experiment, they have to shut off the device.

[Time Stamp: 00:58] Therefore, we cannot say this is an operator's error.

[Time Stamp: 01:03] The second violation: April 26th 0 hours and 28 minutes AM: automatic control conversion.

[Time Stamp: 01:13] Since the operator did not switch on the device which keeps the power at a constant level, the power dropped and the reactor became unstable.

[Time Stamp: 01:24] This was obviously an operation error.

[Time Stamp: 01:28] The third violation: the control rods were pulled out too far.

[Time Stamp: 01:33] They wanted to experiment at a low power output, but they had brought the power too far down.

[Time Stamp: 01:39] In keeping with the character of this reactor, in order to maintain the power, they had no other way but to pull out the control rods.

[Time Stamp: 01:47] Whatever person ordered the continuation of this experiment is responsible.

[Time Stamp: 01:52] Therefore, it is not the operator's error.

[Time Stamp: 01:56] The fourth violation: One hour 3 to 7 minutes: the addition of main circulation pumps.

[Time Stamp: 02:05] The fourth violation was caused by the addition of two pumps which supplied coolant to the core.

[Time Stamp: 02:11] This caused an excess flow of coolant, which in turn caused the core to become unstable.

[Time Stamp: 02:17] It was planned in the experiment, therefore it is not an operation error.

[Time Stamp: 02:23] Fifth violation: one hour nineteen minutes 58 seconds: the bypassing of the automatic shutdown for the steam separator.

[Time Stamp: 02:33] This was ordered for the continuation of the experiment.

[Time Stamp: 02:36] Therefore it is not the operator's error.

[Time Stamp: 02:40] The sixth violation: one hour twenty-three minutes 4 seconds: the bypassing of the automatic shutdown system of the reactor

[Time Stamp: 02:50] As the turbine slows down, a signal is given to automatically shutdown the reactor.

[Time Stamp: 02:56] This was bypassed, in order to be able to repeat the experiment.

[Time Stamp: 03:00] It was not in the experimental procedures.

[Time Stamp: 03:03] It is the responsibility of the person who forcefully tried to continue the experiment.

[Time Stamp: 03:09] If we examine these six violations, there are only two operator errors.

[Time Stamp: 03:14] A bigger problem is the characteristic of the reactor becoming unstable at low power.

[Time Stamp: 03:20] Despite this characteristic, they forcefully continued this experiment.