This unit was 14 days away from being driven down for good. I could guess that it has not been modernized for a while now.
Originally Posted by qwertymac93
hmm, I'm not too worried, just because the containment was destroyed, doesn't mean the plant is 10 minutes to melt down. also, i think the "maximum allowed radiation" is a bit lower then what a full grown adult can really handle, small children might have problems though, IF the levels they are quoting actually reach us, that is...
1 mSv/h (the latest report says it's down to 70 mSv/h. Background radiation meters are offline so these are hand metered somewhere.) is nothing that a healthy adult human can't stand, but everything counts.
When parts of your DNA breaks, sometimes it doesn't get fixed right and it causes a mutation in your DNA. But that doesn't mean you will die in cancer.
Dosage of 50 mSv / year is pretty common for a class A radiation worker around the world. Some plants doesn't allow you to get more then 15 mSv / year, which is good and archievable (again, some plants).
ALARA is for human, from humans.
Originally Posted by i_hax
IIRC Banana's contain a lot of potassium, some of which is a naturally occuring radioactive isotope.
Radioactive decay in a banana is far away from what got released from that unit today.
They still might use sea water with added boron (to keep the fuel under critical and prevent radiation) as a coolant. Clean water just became a luxury in Japan.
Prevent melting is the primary misison, but this adds secondary problems.
Venting pressure from the containment means that some contamination do appear outside the plant. Iodine 131 isotope has a half time of 8 days, but cesium 137 has 30 years half time. Some can be filtered before releasing.
There seems to be high pressure in the containment of Fukushima I - 1, 2 and 3. It's not over yet.