For beta-gamma radiation, Sievert==Gray. Gray is the unit that is actually measured, Sievert is calculated from the Gray-measuremeant using some assumptions. For beta-gamma radiation, a human adult and the radiation source outside of the human adult, these assumptions lead to Sv==Gy.
Ah, you're absolutely correct, my mistake. I will note that 6 Gy is not a hard limit, and it seems there can be effects from as little as 3 Gy, so beta burns aren't ruled out by the estimated dose here. Presumably they're not too bad though, hence the low estimated dose and varying reports over whether there were actually burns or not.
So the workers recieved beta burns, which occur at exposures of beta radiation above 6 sievert, but the workers only recieved 170 millisieverts, therefore something doesn't add up.
As noted by elgarak, and the article in question which is what I was pointing out, their
feet received the large dose. I'm not entirely sure what the lower number means, it's either as elgarak says and simply the full body equivalent given the dose to the feer, or it could mean that that's what their bodies received in addition to the dose their feet received.
They could have avoided the beta burns by wearing the proper clothing, ie "plastics" or by taking the proper beta surveys in the area so they knew what the hazards were.
That supports my accusation that they weren't provided the proper safety equipment and the proper radiation surveys were not taken.
Except in your last post you just said that accusation was a mistake and it was the workers' fault for not using the equipment they had properly. Make up your mind.
The 200 millisievert per hour reading may indeed be a phantom, but that level is entirely consistant with the events as they have occured, and I have seen 90 millisieverts per hour radiation levels at a plant with no suspected fuel element defects, let alone totally drained reactor cores.
Sure, it's not an unreasonable number. That's not the point. The point is that you just claimed that that was what the workers were exposed to, and you were wrong. That was a different measurement in a different building at a different time. Plausible or not, it wasn't a measurement of what happened to these workers.
Worse than chernobyl? How?
Well, Chernobyl had radiation dispersed over half of Europe, but the area around the actual site was relatively sparsely populated. Japan is much more densely populated, so a similar accident could have much worse consequences in the area, followed by the radiation being dispersed over China where people may be less able to cope. For example, many Welsh farmers weren't allowed to sell lambs raised in certain areas (and a few still aren't), but were compensated by the government. What are the chances of China successfully implementing similar restrictions, or actually compensating the billions of people who might be affected?
The ideas of Hollywood explosions and Fallout-style wasteland that some people seem to have are going rather too far, but even if the actual accident isn't any worse, the consequences could still be pretty bad. And despite the generally bad reporting, it does look like things really aren't going all that well at the moment.
Precautionary principle. very low radioactivity effect on human is not very well known, especially young human. All we know we mostly know due to air nuclear testing and nuclear attack on Hiroshima and Nagasaki.
Well, we know quite a bit due to medical use of radiation as well as studies on people who worked with it before there was any safety at all - watchmakers who used to use radioactive paint so they'd glow in the dark is quite a big one. But you're correct that we don't know a huge amount since it's kind of difficult to come up with a vaguely ethical systematic study.
So in case of not knowing you err on the very safe side.
Importantly, very much this. I've started
a thread about this before. Basically, safety levels are currently set orders of magnitude below where they probably could. So when you see things saying radiation was measured at 100 or 1000 times above the safety limit, that means that actually there's still really no risk because we're so incredibly cautious about it. Obviously it's still not a good thing, since whatever the limit it we should be able to control things properly so we don't hit them - going over the limit is a sign that there's a problem. But there's no need for instant panic as soon as things go over the limit - it's a limit where everything is absolutely guaranteed safe with no question below it, not one where everyone dies the instant you pass it.
