3 ms·

> Research says: all of it. Nobody should have been evacuated. That's easy to say in hindsight. How do you make a judgement about that in the hours/days after

by audunw 6y ago

> Research says: all of it. Nobody should have been evacuated. That's easy to say in hindsight. How do you make a judgement about that in the hours/days after the accident? The better-safe-than-sorry approach is probably to evacuate whenever there is a nuclear accident where the building is damaged. But there should be efforts to set up evacuation plans that's not as panicked and doesn't lead to so many deaths.

esjeon 6y ago
Yeah, it literally took years before we can reach this conclusion, even if the conclusion is absolutely reliable. (We still need to observe like 50 more years, haha.) That's the current limitation of our technology. If we could measure radiation levels in a large scale with high resolution within, say, few hrs/days, maybe we didn't have to evacuate all those people. We can't, so we should.
jjk166 6y ago
By studying past incidents which are similar and creating accurate models to predict what will happen based on the data you can rapidly access. If you have a whole bunch of radiation sensors spread around your nuclear plant, you know the level of radiation that people are likely to be exposed to in the near future. If you know the effects of radiation on people, you can predict the health consequences of allowing them to be exposed. If you have records of increased death rates in various evacuations, you can predict the cost of evacuating in this instance. Compare the cost of the two options, go with the better one. It would be one thing if it was the early days of nuclear power and no one knew what the effects of radiation were, and no one had ever considered the possibility of an accident, but this is a mature technology which people have spent decades studying in close detail. People knew at the time that the evacuation plan was a bad idea, and this current report comes as no surprise. By simply assuming that the better-safe-than-sorry approach was to evacuate rather than consulting models based on data, those in charge killed a lot of people.
- fomine3 6y ago
  It's impossible to estimate future max radiation when the plant is not under control. Fukushima pref is 3rd largest prefecture in Japan and not so many people is escaped at the incident. I believe enough number of people had escaped as a result.
  - jjk166 6y ago
    Hogwash. This wasn't some rapid emergency where they lost control of the plant, the reactors shut down properly during the earth quake and most systems were fine. The problem was the tsunami took out several of the backup generators which needed to power the cooling pumps when the reactors weren't producing power and there was no connection to the grid (actually several generators had been moved in 1990 to higher ground and survived the tsunami, but their switching station was kept in the old, unprotected building so they still couldn't provide power). It took days for the reactors to overheat. Radiation levels were being monitored both on the ground and by aircraft, the problem was this data was ignored - in many cases people were evacuated into areas with more intense radiation. Of course when dealing with unknowns your predictions have error bars, but you can most certainly still make valid estimates, and there is no excuse for not doing so.
mpweiher 6y ago
> That's easy to say in hindsight. This was in response to someone claiming the response was correct in hindsight. It was not. Furthermore, there actually was information available beforehand, if nothing else than at least the data from Chernobyl, where the negative health-effects of the evacuation also vastly exceeded the negative health-effects of radiation. In fact the same study concluded that only a fraction of the evacuation was justified (though more than zero as was the case in Fukushima). And that was with a reactor without a proper containment vessel. Last I checked, the Fukushima primary containment vessels weren't breached (the hydrogen explosions blew the roof off the secondary containment, which I think was designed to fail first in order to protect the primary containment vessel inside it from overpressure). So the risk was far less. It was also a fairly slow-moving process. > The better-safe-than-sorry approach [..] ...is exactly what got us into trouble, because we have a skewed, non-reality-based perception of what "safe" is in the context of nuclear power. I can't really tell, but it seems that the danger from the nuclear plant is perceived to be something akin to that from an atomic bomb: sudden/immediate, very lethal and horrible. It's not. Even in the (initially expected) worst case from Chernobyl, the expected health effects were an increase in cancer mortality in later life that even in that worst case would be extremely hard to detect statistically, stemming from prolonged exposure to slightly elevated levels of ionising radiation. The actual measured health effects were far less pronounced than that initially expected worst case. The WHO did a report every 10 years after the disaster. Each time, as actual data came in, they massively downgraded the expected death toll from the accident. > But there should be efforts to set up evacuation plans that's not as panicked and doesn't lead to so many deaths. Yes. And those efforts need to balance the actual risk of staying in place, which is often small to negligible, against the very real consequences of the evacuation. UPDATE: https://www.sciencemag.org/news/2021/03/physician-has-studied-fukushima-disaster-decade-and-found-surprising-health-threat https://www.sciencemag.org/news/2021/03/physician-has-studie...

by audunw 6y ago

esjeon 6y ago

Yeah, it literally took years before we can reach this conclusion, even if the conclusion is absolutely reliable. (We still need to observe like 50 more years, haha.) That's the current limitation of our technology. If we could measure radiation levels in a large scale with high resolution within, say, few hrs/days, maybe we didn't have to evacuate all those people. We can't, so we should.

jjk166 6y ago

By studying past incidents which are similar and creating accurate models to predict what will happen based on the data you can rapidly access. If you have a whole bunch of radiation sensors spread around your nuclear plant, you know the level of radiation that people are likely to be exposed to in the near future. If you know the effects of radiation on people, you can predict the health consequences of allowing them to be exposed. If you have records of increased death rates in various evacuations, you can predict the cost of evacuating in this instance. Compare the cost of the two options, go with the better one. It would be one thing if it was the early days of nuclear power and no one knew what the effects of radiation were, and no one had ever considered the possibility of an accident, but this is a mature technology which people have spent decades studying in close detail. People knew at the time that the evacuation plan was a bad idea, and this current report comes as no surprise. By simply assuming that the better-safe-than-sorry approach was to evacuate rather than consulting models based on data, those in charge killed a lot of people.

fomine3 6y ago
It's impossible to estimate future max radiation when the plant is not under control. Fukushima pref is 3rd largest prefecture in Japan and not so many people is escaped at the incident. I believe enough number of people had escaped as a result.
- jjk166 6y ago
  Hogwash. This wasn't some rapid emergency where they lost control of the plant, the reactors shut down properly during the earth quake and most systems were fine. The problem was the tsunami took out several of the backup generators which needed to power the cooling pumps when the reactors weren't producing power and there was no connection to the grid (actually several generators had been moved in 1990 to higher ground and survived the tsunami, but their switching station was kept in the old, unprotected building so they still couldn't provide power). It took days for the reactors to overheat. Radiation levels were being monitored both on the ground and by aircraft, the problem was this data was ignored - in many cases people were evacuated into areas with more intense radiation. Of course when dealing with unknowns your predictions have error bars, but you can most certainly still make valid estimates, and there is no excuse for not doing so.

mpweiher 6y ago

> That's easy to say in hindsight. This was in response to someone claiming the response was correct in hindsight. It was not. Furthermore, there actually was information available beforehand, if nothing else than at least the data from Chernobyl, where the negative health-effects of the evacuation also vastly exceeded the negative health-effects of radiation. In fact the same study concluded that only a fraction of the evacuation was justified (though more than zero as was the case in Fukushima). And that was with a reactor without a proper containment vessel. Last I checked, the Fukushima primary containment vessels weren't breached (the hydrogen explosions blew the roof off the secondary containment, which I think was designed to fail first in order to protect the primary containment vessel inside it from overpressure). So the risk was far less. It was also a fairly slow-moving process. > The better-safe-than-sorry approach [..] ...is exactly what got us into trouble, because we have a skewed, non-reality-based perception of what "safe" is in the context of nuclear power. I can't really tell, but it seems that the danger from the nuclear plant is perceived to be something akin to that from an atomic bomb: sudden/immediate, very lethal and horrible. It's not. Even in the (initially expected) worst case from Chernobyl, the expected health effects were an increase in cancer mortality in later life that even in that worst case would be extremely hard to detect statistically, stemming from prolonged exposure to slightly elevated levels of ionising radiation. The actual measured health effects were far less pronounced than that initially expected worst case. The WHO did a report every 10 years after the disaster. Each time, as actual data came in, they massively downgraded the expected death toll from the accident. > But there should be efforts to set up evacuation plans that's not as panicked and doesn't lead to so many deaths. Yes. And those efforts need to balance the actual risk of staying in place, which is often small to negligible, against the very real consequences of the evacuation. UPDATE: https://www.sciencemag.org/news/2021/03/physician-has-studied-fukushima-disaster-decade-and-found-surprising-health-threat https://www.sciencemag.org/news/2021/03/physician-has-studie...