880 Millisieverts/Hr Radiation on Reactor 2's 5th Floor at #Fukushima, Found by Quince the Robot

Quince No.2 did not find visible damage to the building interior, but got 505.6 millisieverts of radiation exposure for the 4-hour work.

Earlier, human workers went down to the Torus Room of Reactor 2 trying to photograph the level of water inside the Suppression Chamber with an infrared camera to estimate the location of the leak. They were unsuccessful, probably due to steam on the surface of the water.

Reactor 2 is more scary to me than Reactor 3 or Reactor 4. No visible damage anywhere, yet it has released the most radioactive materials. Thermocouples keep failing, and such a high radiation out of nowhere.

From Sankei Shinbun (6/13/2012):

２号機５階で毎時８８０ミリシーベルト　福島第１

Fukushima Daiichi (I) 880 Millisieverts/hour on 5th floor of Reactor 2

東京電力は１３日、福島第１原発２号機の原子炉建屋内部をロボットを使って調査し、５階の原子炉の真上にあたるコンクリート床付近で、毎時８８０ミリシーベルトの放射線量を計測したと発表した。作業員の５年間の被曝線量上限にあたる１００ミリシーベルトに約７分間で達する値で、東電は「５階に人が立ち入っての作業は困難」とみている。建屋内に目立った損傷はなかったという。

TEPCO announced on June 13 that it conducted the survey of the interior of the Reactor 2 building using a robot, which measured the 880 millisieverts/hour radiation near the concrete floor on the 5th floor right above the reactor. The 5-year cumulative maximum radiation exposure for nuclear workers (100 millisieverts) would be reached in about 7 minutes at that location. TEPCO thinks it will be difficult for [human] workers to enter the 5th floor. According to the company, there was no visible damage to the interior of the building.

国産の災害対策支援ロボット「クインス」の改良型が、５階まで自走して測定した。今回、最高値を計測した場所のコンクリート床の厚さは約２メートルで、格納容器の上端から約３．５メートル離れているという。

The improved version of "Quince", robot developed in Japan for disaster response support, went up to the 5th floor and measured the radiation. The concrete floor with the highest radiation level this time is about 2-meter thick, and about 3.5 meter away from the top of the Containment Vessel.

約４時間にわたる調査で、ロボットの被曝（ひばく）線量は５０５．６ミリシーベルトで、作業員９人の被曝線量は最大で３．９５ミリシーベルトだった。

The robot got 505.6 millisieverts of radiation exposure in the 4-hour survey, and the 9 [human] workers got the max 3.95 millisieverts.

There is no data yet on TEPCO's sites (English or Japanese). I'll post when they do.

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