I watched the 5 part docudrama about Chernobyl this week whilst on holiday.
I didn't realise how close we were (measured in hours) to a catastrophe on a scale never before seen. It would changed the world forever- millions dead, even more millions dying and huge areas of Northern Europe uninhabitable for the foreseeable future. A truly scary program. Jules

I watched it some time ago, wow the effects of the radiation on those poor firemen who had no idea what they were dealing with.

The true extent of it will probably never be known as it did seem the Soviets in charge were keeping it from the people & denying there was a problem, those military personnel having to go on the roof where even a robotic machine could not survive for so many seconds each to literally throw the reactor debris back into the reactor so they could encase it in concrete in the end.

A very scary program on just how lethal radiation is.

The results are known, though Chernobyl was in the Soviet Union as was Ukraine it isn't now and there is free entry for anyone to the area with permissions, it's even a tourist trail with limited access time due to the ongoing radiation. the programme has some inaccuracies and obvious drama, yes many were killed and the danger to personnel not given at the time, however there was no threat to the world any more than the Japanese plant was, the explosion was due to loss of cooling flow giving off super heated steam which blew apart the reactor and the reaction stopped however the cloud of steam rising in the atmosphere then irradiated the local countryside and was carried across to the west gradually degrading.
When it reached the UK there was still enough radiation to cause problems of higher than normal radiation in some animal products due to the irradiated rain and grass feeders. The really dangerous radiation has a range of a few metres and degrades in air but still is present in solid materials which are and still be dangerous for many decades. my PC is slightly to the right of Genghis
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From the program it seems that the initial explosion was one thing but the sand/boron dropped by helicopter to put out the fire had the effect of sealing in the heat generated by the molten core. The scientists calculated that the core would melt through the concrete base and into tanks, which should have been empty but now were full of water from the attempts to dowse the fire, within 72 hours. The resulting explosion (2-4 Mega tonnes) would take out the 3 remaining nuclear reactors and eject their cores into a shock wave spreading out over a 200km radius - likely to be fatal to everyone within that distance including the entire populations of Kiev and Minsk. Belarus and Ukraine would not be habitable for over a 100 years. All the countries to Germany would be severely affected.

As has been said much of the Chernobyl data is freely available.
The program indicated where artistic licence was used for dramatic effect. Jules

I suspect that the documentary was a bit exaggerated as ever. I was working with the UK atomic energy authority when this happened and there was no sign of panic and everyone was fairly laid back about it. They were more concerned with radiation leakage from Sellafield at the time and the radiation from Chernobyl was less of a problem. We did have a reactor with a somewhat similar design (since decommissioned) but it didn't have a positive void coefficient so that was ok. 😀 3 x FL1 2 manual + 1 auto
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2 to 4 mega tons explosion is in the nuclear fusion range not fission range, accidents from nuclear fission cannot result in a fusion range explosion. my PC is slightly to the right of Genghis
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Yes you are correct. The largest fission bombs were in the kiloton range.

But (and I'm only quoting the program) this explosion and shock wave would be caused by the near instantaneous vaporisation of approximately 7000 tonnes of water rather than nuclear fission per se. Jules

dorsetfreelander wrote:

I suspect that the documentary was a bit exaggerated as ever. I was working with the UK atomic energy authority when this happened and there was no sign of panic and everyone was fairly laid back about it. They were more concerned with radiation leakage from Sellafield at the time and the radiation from Chernobyl was less of a problem. We did have a reactor with a somewhat similar design (since decommissioned) but it didn't have a positive void coefficient so that was ok. 😀

lots of info here

https://en.wikipedia.org/wiki/Chernobyl_disaster#Explosion_risk Jules

And this is why we are buying the Chinese technology (and manpower mostly) for our new NPs.

No worries  Regards

David

Lovely i6 has now gone, but not me......

Please let me know if anything in my post offends you, as I may wish to offend you again......

jules wrote:

dorsetfreelander wrote:

I suspect that the documentary was a bit exaggerated as ever. I was working with the UK atomic energy authority when this happened and there was no sign of panic and everyone was fairly laid back about it. They were more concerned with radiation leakage from Sellafield at the time and the radiation from Chernobyl was less of a problem. We did have a reactor with a somewhat similar design (since decommissioned) but it didn't have a positive void coefficient so that was ok. 😀

Was that the Thorpe reactor ?
IIRC There was one that caught fire and the country was saved from significant radioactive contamination because a scientist insisted on filters being added on the chimneys which stopped the radioactive dust escaping.

I thought the new Nuclear power stations were French technology and Chinese cash, not sure what went wrong with AGR reactors which were to be the future before the last Labour government decided nuclear wasn't the way to go, had it decided it was the way to go we would now have them working and a lot cheaper my PC is slightly to the right of Genghis
2012 HSE SD4 In Orkney Grey now gone, best car ever.

We should have gone with the Finnish design but it was too expensive, went for the Chinese design.......SWMBO had the reports written for them.

And that’s all I can say on the matter  Regards

David

Lovely i6 has now gone, but not me......

Please let me know if anything in my post offends you, as I may wish to offend you again......

dorsetfreelander wrote:

Incidentally Thorpe is not a reactor but stands for thermal oxide reprocessing plant