They are finally putting out some numbers in milliSeiverts, but these range all over the place. From notes off various reports from RT and AJE. Near the plants from 4-87mSv/hr. Reported at 0.5-1.04mSv/hr at some further distance.
``Symptoms of acute radiation (within one day):[16]
0 - 0.25 Sv (0 - 250 mSv): None 0.25 - 1 Sv (250 - 1000 mSv): Some people feel nausea and loss of appetite; bone marrow, lymph nodes, spleen damaged. 1 - 3 Sv (1000 - 3000 mSv): Mild to severe nausea, loss of appetite, infection; more severe bone marrow, lymph node, spleen damage; recovery probable, not assured.''
http://en.wikipedia.org/wiki/Sievert
So, you can tell, after unit changes, times, distances, averages and comparisons it is difficult to sort this out. I quoted the part that looked easiest. At 87mSv/hr x 24 = 2088. At 4mSv/hr x 24 = 96. But the latter might be within the area that people have been stuck in for several days, so 96 x 3 = 288. While the former figure (hopefully) has been mitigated by radiation gear.
The Sievert is a complicated unit that means equivalent dose. It is related to the element and isotope emitting the radiation and the tissue characteristics. But this relationship is based on many years of study in biophysics and medicine. It is an active area of research---probably soon to be given a big boost by Japan.
The Japanese govt upgraded the disaster to level 5, which seems absurd.
Christian Parenti writes, ``The NRC needs an overhaul-now. And our fleet of leaky old plants needs to be decommissioned.''
http://www.thenation.com/article/159300/warning-japan
I agree, except I've been trying to sort through the words and their meanings. Decommissioned is only one step. The next step is to dismantle the plant and prepare the materials (dry cask) for relocation in some stable, deep cave somewhere (in Neveda, Utah, Idaho Arizona or Texas). The step after that is the toxic clean up of the land of the former plant.
Example. Humbolt Bay listed status on the UCS chart was dismantled. It was `shutdown' permanently in July 1976. Here's the current wiki:
``In 2004 Pacific Gas and Electric Company announced that three nuclear fuel rods were unaccounted for due to conflicting records of their location. The fuel rods were never accounted for, though PG&E investigators believe that they are still onsite in a storage pool. The investigation is believed to have cost one million dollars.[1]
In December 2008, PG&E finished moving the spent nuclear fuel into dry cask storage on site. The next step is the decommissioning of the plant, planned to begin in 2010 along with the two original fossil-fuel-powered steam-turbine generators on site. The plant began being powered by an array of modern, multi-fuel Wärtsilä reciprocating engine-generators in late 2010. The work to dismantle the older turbine generators and continued dismantling of the nuclear side of the operations is scheduled to finish by April 2013.''
http://en.wikipedia.org/wiki/Humboldt_Bay_Nuclear_Power_Plant
CG