Radiation Injuries:
One Tepco worker working within the reactor building of Fukushima Daiichi unit 3 during "vent work" was taken to hospital after receiving radiation exposure exceeding 100 mSv, a level deemed acceptable in emergency situations by some national nuclear safety regulators.
So one worker got the allowed emergency dose of 100 mSv and... was sent to the hospital! The Japanese authorities have raised the allowable emergency dose to 250 mSv. The 100 mSv corresponds to a risk 0.1 Sv x 0.05 = 0.005 cancer induction. So very small risk and one worker.
General Status:
NEI UPDATE AS OF 11:35 A.M. EDT, THURSDAY, MARCH 17:
Fukushima Daiichi
The reactors at the Fukushima Daiichi plant are in stable condition and are being cooled with seawater, but workers at the plant continue efforts to add cooling water to fuel pools at reactors 3 and 4.
The status of the reactors at the site is as follows:
Reactor 1’s primary containment is believed to be intact and the reactor is in a stable condition. Seawater injection into the reactor is continuing.
Reactor 2 is in stable condition with seawater injection continuing. The reactor’s primary containment may not have been breached, Tokyo Electric Power Co. and World Association of Nuclear Operators officials said on Thursday. Containment pressure is at 65 psig, an indication that containment has not been breached.
Access problems at the site have delayed connection of a temporary cable to restore offsite electricity. The connection will provide power to the control rod drive pump, instrumentation, batteries, and power to the control room. Power has not been available at the site since the earthquake on March 11.
Reactor 3 is in stable condition with seawater injection continuing. The primary containment is believed to be intact. Pressure in the containment has fluctuated due to venting of the reactor containment structure, but has been as high as 83 psig.
TEPCO officials say that although one side of the concrete wall of the fuel pool structure has collapsed, the steel liner of the pool remains intact, based on aerial photos of the reactor taken on March 17. The pool still has water providing some cooling for the fuel, however helicopters dropped water on the reactor four times during the morning (Japan time) on March 17. Water also was sprayed at reactor 4 using high pressure water cannons.
Reactors 5 and 6 were both shut down before the quake occurred. Primary and secondary containments are intact at both reactors. Temperature instruments in the spent fuel pools at reactors 5 and 6 are operational, and temperatures are being maintained at about 62 degrees Celsius. TEPCO is continuing efforts to restore power at reactor 5.
Fukushima Daini
All four reactors at the Fukushima Daini plant have reached cold shutdown conditions with normal cooling being maintained using residual heat removal systems.
DOSE INFORMATION (Kevin Robb)
There's some more info being posted about doses, including near the plant:
This site is, I believe, for the command center in Fukushima:
http://tinyurl.com/4zs44yh
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