Ministry of Health, Labour and Welfare

Exposure Dose Distribution of the Workers at
Fukushima Daiichi Nuclear Power Plant

Updated on 30 April 2016


1. Number of Workers (Later than 11 March 2011)

 
Persons
Increase
Emergency Workers(*)
Updated on
Total Workers
46,956 192 19,675 As of 31 March 2016(Obtained on 30 April)
TEPCO
4,712 6 3,636
Contractors
42,244 186 16,039

(*) As of November 2014; Including workers to whom emergency dose limits apply

2. Radiation Exposure Dose Distributions

(1)The distribution of external exposure dose of the workers during the last 3 months
   (Numbers of workers who entered each area every month)

Effective dose (E) mSv January 2016 February 2016 March 2016
TEPCO Contractors Total TEPCO Contractors Total TEPCO Contractors Total
100<E 0 0 0 0 0 0 0 0 0
75<E≤100 0 0 0 0 0 0 0 0 0
50<E≤75 0 0 0 0 0 0 0 0 0
20<E≤50 0 0 0 0 0 0 0 0 0
10<E≤20 0 4 4 0 12 12 0 14 14
5<E≤10 0 60 60 0 78 78 0 101 101
1<E≤5 38 1,194 1,232 49 1,461 1,510 42 1,245 1,287
E≤1 1,108 8,070 9,178 1,128 7,896 9,024 1,022 7,945 8,967
Total 1,146 9,328 10,474 1,177 9,447 10,624 1,064 9,305 10,369
Maximum(mSv) 3.30 16.00 16.00 4.70 12.36 12.36 2.71 13.42 13.42
Average(mSv) 0.20 0.51 0.48 0.22 0.59 0.55 0.18 0.56 0.52

(*)Exposure doses and the number of workers are subject to change due to the replacement of accumulated doses measured using PAD with monthly doses measured using an integrating dosimeter and the reflection of values for workers wearing only an integrating dosimeter (e.g., workers working only within a seismically isolated building).

(2)Combined Cumulative Effective Dose from March 2011 (Internal and External)

Effective Dose (E) mSv
March 2011- February 2016
March 2011- March 2016
Difference
TEPCO Contractors Total TEPCO Contractors Total TEPCO Contractors Total
250<E 6 0 6 6 0 6 0 0 0
200<E≤250 1 2 3 1 2 3 0 0 0
150<E≤200 26 2 28 26 2 28 0 0 0
100<E≤150 117 20 137 117 20 137 0 0 0
75<E≤100 318 293 611 321 312 633 3 19 22
50<E≤75 329 1,775 2,104 327 1,797 2,124 -2 22 20
20<E≤50 633 6,471 7,104 633 6,513 7,146 0 42 42
10<E≤20 618 5,707 6,325 620 5,793 6,413 2 86 88
5<E≤10 508 5,467 5,975 507 5,442 5,949 -1 -25 -26
1<E≤5 898 9,600 10,498 907 9,616 10,523 9 16 25
E≤1 1,252 12,721 13,973 1,247 12,747 13,994 -5 26 21
Total 4,706 42,058 46,764 4,712 42,244 46,956 6 186 192
Maximum(mSv) 678.80 238.42 678.80 678.80 238.42 678.80 - - -
Average(mSv) 22.41 11.68 12.76 22.43 11.75 12.83 - - -
(*) Number of new comers in March 2016 was 192.
(*) There has been no significant internal exposure reported since October 2011.
(*) Exposure doses and the number of workers are subject to change due to the replacement of accumulated doses measured using PAD with monthly doses measured using an integrating dosimeter and the reflection of values for workers wearing only an integrating dosimeter (e.g., workers working only within a seismically isolated building).

(3) Combined Cumulative Effective Dose from April 2015 (Internal and External)

Effective Dose (E) mSv April 2015 - February 2016 April 2015 - March 2016 Difference
TEPCO Contractors Total TEPCO Contractors Total TEPCO Contractors Total
100<E 0 0 0 0 0 0 0 0 0
75<E≤100 0 0 0 0 0 0 0 0 0
50<E≤75 0 0 0 0 0 0 0 0 0
20<E≤50 5 517 522 6 588 594 1 71 72
10<E≤20 42 1,762 1,804 52 1,940 1,992 10 178 188
5<E≤10 110 2,175 2,285 107 2,247 2,354 -3 72 69
1<E≤5 509 5,163 5,672 539 5,107 5,646 30 -56 -26
E≤1 1,020 6,553 7,573 992 6,599 7,591 -28 46 18
Total 1,686 16,170 17,856 1,696 16,481 18,177 10 311 321
Maximum(mSv) 23.10 43.20 43.20 23.94 43.20 43.20 - - -
Average(mSv) 1.73 4.26 4.02 1.83 4.50 4.25 - - -
(*) Exposure doses and the number of workers are subject to change due to the replacement of accumulated doses measured using PAD with monthly doses measured using an integrating dosimeter and the reflection of values for workers wearing only an integrating dosimeter (e.g., workers working only within a seismically isolated building).

(4)Combined Cumulative Effective Dose of Workers to Whom Emergency Dose Limits Apply*

Effective dose (E) mSv
Jan. 2016
Feb. 2016
Mar. 2016
March 2011- March 2016
100<E 0 0 0 1
75<E≤100 0 0 0 191
50<E≤75 0 0 0 233
20<E≤50 0 0 0 267
10<E≤20 0 0 0 186
5<E≤10 0 0 0 129
1<E≤5 0 0 0 145
E≤1 0 0 0 51
Total 0 0 0 1,203
Maximum(mSv) - - - 102.69
Average(mSv) - - - 36.49
(*) Workers under the application of the emergency dose limit (100mSv) shown in Article 7 of the Ordinance on Prevention of Ionizing Radiation Hazards.
Specifically, they are workers engaged in work to maintain the function of cooling reactors or spent fuel tanks or to maintain the function to control or prevent the release of a huge amount of radioactive material due to trouble or a breakdown at a reactor facility, in an area where radiation dose rates exceed 0.1 mSv/h, around any reactor facilities, steam turbines and related facilities, and the vicinity thereof in the NPP. Until now, all designated workers have been TEPCO employees.
(*) The monthly number of workers to whom emergency dose limits apply is the number of workers who have filed applications as such. However, the cumulative number for the period between March 2011 and March 2016 includes those whose designation was removed.
(*) Exposure doses and the number of workers are subject to change due to the replacement of accumulated doses measured using PAD with monthly doses measured using an integrating dosimeter and the reflection of values for workers wearing only an integrating dosimeter (e.g., workers working only within a seismically isolated building).
(*) The results of re-evaluating committed doses in March 2011 reveal that maximum cumulative effective doses for the period between March 2011 and March 2016 exceeded 100.

Archives

Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 30 April 2016).
PDF 88KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 31 March 2016).
PDF 81KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 29 February 2016).
PDF 76KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 29 January 2016).
PDF 82KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 25 December 2015).
PDF 76KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 30 November 2015).
PDF 76KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 30 October 2015).
PDF 76KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 30 September 2015).
PDF 76KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 31 August 2015).
PDF 76KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 31 July 2015).
PDF 92KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 30 June 2015).
PDF 83KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 29 May 2015).
PDF 71KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 1 May 2015).
PDF 76KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 31 March 2015).
PDF 86KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 27 February 2015).
PDF 53KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 30 January 2015).
PDF 53KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 26 December 2014).
PDF 63KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 1 December 2014).
PDF 63KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 31 October 2014).
PDF 63KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on September 2014).
PDF 64KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on August 2014).
PDF 64KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on July 2014).
PDF 64KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 30 June 2014).
PDF 63KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 30 May 2014).
PDF 58KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 30 April 2014).
PDF 64KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 31 March 2014).
PDF 54KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 28 February 2014).
PDF 32KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 31 January 2014).
PDF 86KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 26 December 2013).
PDF 86KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 29 November 2013).
PDF 86KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Plant
(Updated on 31 October 2013).
PDF 86KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Station
(Updated on 30 September 2013)
PDF 85KB
Exposure Dose Distribution of the Workers at Fukushima Daiichi Nuclear Power Station
(Updated on 30 August 2013)
PDF 79KB


Please leave your message & inquiry to: www-admin@mhlw.go.jp

1-2-2 Kasumigaseki Chiyoda-ku Tokyo, 100-8916 Japan Tel: 03-5253-1111
Copyright c Ministry of Health, Labour and Welfare, All Right reserved.