Radiation Exposure Data for Nuclear Power Plant Workers (Fiscal Year 2012)

On October 9, 2013, the Nuclear Regulatory Agency published the FY2012 report on the management of worker radiation exposure at nuclear power facilities. www.nsr.go.jp/committee/kisei/data/0026_03.pdf  (in Japanese)

Table 1 shows the data on radiation dose management for workers in nuclear reactor buildings of nuclear power plants, based on the report’s data for “management of radioactive wastes and management of radiation doses of workers engaged in radiation-related jobs at nuclear reactor facilities for generating power for commercial use and those for generating power for research and development,” during the period from April 2012 through March 2013.

Previously, the data for Tokyo Electric Power Company’s (TEPCO) Fukushima Daiichi Nuclear Power Station and the Fukushima Daini Nuclear Power Station remained un-submitted, due to “a delay in dosage calculation by TEPCO’s subcontractors caused by the negative effects of the 2011 Great East Japan Earthquake.” The data was finally submitted on April 26, 2013.

Table 2 shows the revised report published on July 5. Earlier, the Ministry of Health, Labor and Welfare closely examined the internal exposure data in the original report in response to complaints from the World Health Organization and other international organizations about the data. As a result, the ministry discovered that there were a number of discrepancies between the data presented by TEPCO and those from its subcontractors. The revised July 5 report contains the re-calculations of the data.

The number of workers at the Fukushima Daiichi Nuclear Power Station who suffered a cumulative radiation exposure of 20 mSv annually totaled 738, consisting of 63 TEPCO employees and 675 subcontractor employees. The maximum annual radiation dose registered by workers stood at 54.1mSv.

Table 3 shows the distribution of annual radiation dose registered by the workers at the Fukushima Daiichi Nuclear Power Station each fiscal year, published by TEPCO. According to our calculations, the workers’ combined exposure doses for March 2011, FY2011, and FY2012 reached an enormously high level of approximately 341 man-Sv. Of these, about 73 percent are doses registered by subcontractor employees.

In most Western countries and South Korea, the central government has the responsibility for managing the radiation doses of workers at nuclear power facilities. In Japan, however, the subcontractors that employ such workers are expected to take responsibility for this. The government is doing nothing except collect the data from the subcontractors. Even after the nuclear accident in Fukushima on March 11, 2011, it is not TEPCO but the subcontractors who are required to manage worker radiation dose and worker health.It is still unclear how the major subcontractors evaluated the radiation doses of the workers employed by the lower and lowest level subcontractors.

Amid the confusion in the wake of the nuclear accident, there was a serious shortage of dosimeters for individual workers. Moreover, many workers lied about their doses, fearing that they might be fired once their doses exceeded the official limit. These incidents indicate that the published data do not correctly reflect the true situation on radiation doses. For many years, we have strongly insisted on the need for the government to unify the management of exposure doses of workers engaged in radiation-related work and take strict responsibility for data management. We called for the creation of such a system even before the March 11 nuclear accident, but the government has thus far totally failed to take the necessary measures.

(Mikiko Watanabe, CNIC)

Plant Attribution Dose level [per person] Collective effective dose Average effective dose Maximum effective dose

5mSv
5mSv 10mSv 15mSv 20mSv 25mSv 30mSv 35mSv 40mSv 45mSv 50mSv
10mSv 15mSv 20mSv 25mSv 30mSv 35mSv 40mSv 45mSv 50mSv (man・Sv) (mSv) (mSv)
Tokai Power Company 309 0 0 0 0 0 0 0 0 0 0 0.00 0.0 0.6
Subcontractor 1016 0 0 0 0 0 0 0 0 0 0 0.07 0.1 4.5
Total 1325 0 0 0 0 0 0 0 0 0 0 0.07 0.1 4.5
Tokai-2 Power Company 354 0 0 0 0 0 0 0 0 0 0 0.04 0.1 2.2
Subcontractor 2092 2 0 0 0 0 0 0 0 0 0 0.32 0.2 5.7
Total 2446 2 0 0 0 0 0 0 0 0 0 0.36 0.1 5.7
Tsuruga Power Company 439 0 0 0 0 0 0 0 0 0 0 0.02 0.1 1.3
Subcontractor 2360 1 0 0 0 0 0 0 0 0 0 0.30 0.1 5.4
Total 2799 1 0 0 0 0 0 0 0 0 0 0.32 0.1 5.4
Onagawa Power Company 479 0 0 0 0 0 0 0 0 0 0 0.01 0.0 0.9
Subcontractor 3479 43 4 0 0 0 0 0 0 0 0 1.10 0.3 12.1
Total 3958 43 4 0 0 0 0 0 0 0 0 1.12 0.3 12.1
Higashidori Power Company 289 0 0 0 0 0 0 0 0 0 0 0.00 0.0 0.1
Subcontractor 747 0 0 0 0 0 0 0 0 0 0 0.01 0.0 1.1
Total 1036 0 0 0 0 0 0 0 0 0 0 0.01 0.0 1.1
Fukushima-1 Power Company 1165 266 90 39 23 16 9 10 2 2 1 7.30 4.5 54.1
Subcontractor 7567 1875 1231 769 254 206 95 104 16 0 0 71.51 5.9 43.1
Total 8732 2141 1321 808 277 222 104 114 18 2 1 78.81 5.7 54.1
Fukushima-2 Power Company 642 0 0 0 0 0 0 0 0 0 0 0.06 0.1 1.5
Subcontractor 2452 17 6 1 0 0 0 0 0 0 0 0.71 0.3 17.2
Total 3094 17 6 1 0 0 0 0 0 0 0 0.77 0.2 17.2
Kashiwazaki
-kariwa
Power Company 1150 0 0 0 0 0 0 0 0 0 0 0.10 0.1 4.3
Subcontractor 4965 31 3 0 0 0 0 0 0 0 0 0.51 0.3 11.4
Total 6115 31 3 0 0 0 0 0 0 0 0 0.61 0.3 11.4
Hamaoka Power Company 791 0 0 0 0 0 0 0 0 0 0 0.06 0.1 3.0
Subcontractor 3980 38 15 0 0 0 0 0 0 0 0 1.45 0.4 15.0
Total 4771 38 15 0 0 0 0 0 0 0 0 1.51 0.3 15.0
Shika Power Company 401 0 0 0 0 0 0 0 0 0 0 0.01 0.0 0.6
Subcontractor 1174 0 0 0 0 0 0 0 0 0 0 0.11 0.1 2.5
Total 1575 0 0 0 0 0 0 0 0 0 0 0.12 0.1 2.5
Shimane Power Company 527 0 0 0 0 0 0 0 0 0 0 0.02 0.0 1.5
Subcontractor 2117 67 0 0 0 0 0 0 0 0 0 1.32 0.6 7.6
Total 2644 67 0 0 0 0 0 0 0 0 0 1.34 0.5 7.6
Tomari Power Company 417 0 0 0 0 0 0 0 0 0 0 0.01 0.0 1.9
Subcontractor 2181 20 0 0 0 0 0 0 0 0 0 0.54 0.2 8.3
Total 2598 20 0 0 0 0 0 0 0 0 0 0.55 0.2 8.3
Mihama Power Company 457 0 0 0 0 0 0 0 0 0 0 0.02 0.0 1.0
Subcontractor 2314 7 0 0 0 0 0 0 0 0 0 0.50 0.2 6.3
Total 2771 7 0 0 0 0 0 0 0 0 0 0.52 0.2 6.3
Takahama Power Company 517 0 0 0 0 0 0 0 0 0 0 0.03 0.1 1.0
Subcontractor 2938 16 0 0 0 0 0 0 0 0 0 0.88 0.3 9.0
Total 3455 16 0 0 0 0 0 0 0 0 0 0.91 0.3 9.0
Ohi Power Company 516 4 0 0 0 0 0 0 0 0 0 0.20 0.4 7.9
Subcontractor 2636 46 3 0 0 0 0 0 0 0 0 1.24 0.5 12.0
Total 3152 50 3 0 0 0 0 0 0 0 0 1.44 0.4 12.0
Ikata Power Company 350 0 0 0 0 0 0 0 0 0 0 0.01 0.0 0.7
Subcontractor 1662 0 0 0 0 0 0 0 0 0 0 0.16 0.1 2.8
Total 2012 0 0 0 0 0 0 0 0 0 0 0.17 0.1 2.8
Genkai Power Company 523 0 0 0 0 0 0 0 0 0 0 0.01 0.0 1.1
Subcontractor 2348 1 0 0 0 0 0 0 0 0 0 0.38 0.2 5.3
Total 2871 1 0 0 0 0 0 0 0 0 0 0.39 0.1 5.3
Sendai Power Company 293 0 0 0 0 0 0 0 0 0 0 0.01 0.0 0.8
Subcontractor 1390 0 0 0 0 0 0 0 0 0 0 0.13 0.1 2.5
Total 1683 0 0 0 0 0 0 0 0 0 0 0.14 0.1 2.5
Commercial
plant total
Power Company 9619 270 90 39 23 16 9 10 2 2 1 7.91 0.8 54.1
Subcontractor 47418 2164 1262 770 254 206 95 104 16 0 0 82.24 1.6 43.3
Total 57037 2434 1352 809 277 222 104 114 18 2 1 90.16 1.4 54.1
                
Fugen Power Company 116 0 0 0 0 0 0 0 0 0 0 0.01 0.1 2.8
Subcontractor 402 5 0 0 0 0 0 0 0 0 0 0.13 0.3 9.4
Total 518 5 0 0 0 0 0 0 0 0 0 0.15 0.3 9.4
Monju Power Company 368 0 0 0 0 0 0 0 0 0 0 0.00 0.0 0.0
Subcontractor 869 0 0 0 0 0 0 0 0 0 0 0.00 0.0 0.0
Total 1237 0 0 0 0 0 0 0 0 0 0 0.00 0.0 0.0
Total Power Company 10103 270 90 39 23 16 9 10 2 2 1 7.92 0.7 54.1
Subcontractor 48689 2169 1262 770 254 206 95 104 16 0 0 82.37 1.5 43.4
Total 58792 2439 1352 809 277 222 104 114 18 2 1 90.31 1.4 54.1
Table1; FY2012 data on radiation exposure of workers at nuclear-reactor facilities for power generation (including Fugen and Monju)

 

  Fukushima-1 Fukushima-2
Fiscal 2010 Fiscal 2011 Fiscal 2010 Fiscal 2011
Total number of workers Power Company 1936 2903 1485 1155
Subcontractor 12127 16993 6422 3634
Total 14063 19896 7907 4789
Collective effective dose(man・Sv) Power Company 53.66 32.01 0.39 0.18
Subcontractor 59.14 145.54 4.43 1.86
Total 112.8 177.56 4.82 2.04
Average effective dose(mSv) Power Company 27.7 11 0.3 0.2
Subcontractor 4.9 8.6 0.7 0.5
Total 8 8.9 0.6 0.4
Table2; Unsubmitted data for TEPCO’s Fukushima Daiichi and Daini Nuclear Power Stations
・Data for the Daiichi Nuclear Power Station was submitted on April 26, 2013 and a revised version submitted on July 5, 2013.
・The revised version of the FY2010 data for the Dai-ni Nuclear Power Station was submitted by TEPCO’s subcontractors on Jan. 18, 2013.
The report on the FY2011 data was under scrutiny on the same day.

 

Level (mSv) ~1 1 5 10 20 50 75 100 150 200 250
Maximum effective dose Average effective dose
5 10 20 50 75 100 150 200 250
From March 2011 to end FY2011 Power Company 796 559 365 491 925 263 179 118 24 1 6 678.80 24.78
Subcontractor 4672 4623 2555 2886 2654 256 64 20 2 2 0 238.42 10.01
FY2012 Power Company 586 579 266 129 62 1 0 0 0 0 0 54.10 4.50
Subcontractor 4241 3326 1875 2000 675 0 0 0 0 0 0 43.30 5.90
Table3; Distribution of radiation dose for Fukushima Daiichi Nuclear Power Station workers for each fiscal year. Published by TEPCO

 

Print Friendly, PDF & Email

You may also like...