On March 22nd, 2011, as a part of monitoring activity of the surrounding 
environments, we conducted nuclide analyses of radioactive materials 
contained in the air which were collected at the site of Fukushima Daiichi 
Nuclear Power Station, which was damaged by the Tohoku- Chihou-Taiheiyou
-Oki Earthquake. As a result, radioactive materials were detected and 
therefore, we summarized the results and reported them to Nuclear and 
Industry Safety Agency (NISA) as well as to the government of Fukushima 
Prefecture.

The analyses results of the three nuclides (Iodine-131, Cesium-134 and 
Cesium-137) are to be released as fixed figures, and the other nuclide 
figures are to be revaluated.
                                                    (Previously announced)

On May 25th, 2011, we conducted nuclide analyses of radioactive materials 
contained in the air which was collected at the site of Fukushima Daiichi 
Nuclear Power Station on the same day. As a result, some radioactive 
materials were detected as described in the appendix. Accordingly, today 
we have summarized the results and reported them to NISA and the 
government of Fukushima Prefecture.

We collected the air near the monitoring post No.5 in order to correspond 
to the changes in power source composition on May 25th, 2011.
We found out that no nuclides (Plutonium-238, Plutonium-239 and 
Plutonium-240) were detected as the result of the analyses of the sample 
of the air which was collected on May 9th, 2011.

We will continuously conduct the same sampling surveys. 

Appendix1: Result of Nuclide Analysis of Radioactive Materials in the Air 
           at the Site of Fukushima Nuclear Power Stations (PDF 52.6KB) 
Appendix2: Fukushima Daiichi Nuclear Power Station: 
           The Result of the Dust Nuclide Analysis(PDF 36.3KB) 
Appendix3: Fukushima Daini Nuclear Power Station: 
           The Result of the Dust Nuclide Analysis(PDF 36.1KB) 
Appendix4: Measurements of plutonium in the air in Fukushima Daiichi 
           Nuclear Power Station(PDF 29.8KB)