Measurement of radiation and radioactivity in Tokyo Port

Dec.28,2017 13:00 update

 As a countermeasure against harmful rumors related to the accident at TEPCO's Fukushima Daiichi Nuclear Power Plant, we have decided to monitor the radiation in the atmosphere at each container wharf in Tokyo Port and radioactivity in the seawater in the Port and radiation dose on the surface of containers through cooperation with Tokyo Port Terminal Corporation. The measurement result shall be disclosed on this website. 

・April 14, 2011 ~ May 8, 2011

atmosphere (every Monday and Thursday), seawater(from Monday to Friday)

・May 9, 2011 ~ March 31, 2013

atmosphere, seawater, container surface(from Monday to Friday)

・April 1, 2013 ~March 31, 2014

atmosphere, seawater, container surface(every Monday and Thursday)

・April 1, 2014 ~March 31, 2017

atmosphere, seawater, container surface(every Thursday (or Friday sometimes))

・April 1, 2017~

atmosphere, seawater, container surface(biweekly Thursday)

* business days only

 Map of monitoring site

Map of monitoring site

・The measurement for radiation in the atmosphere and at container surfaces are conducted with support of Nippon Kaiji Kentei Kyokai, and for radioactivity in the seawater, Tokyo Metropolitan University.
・Amount of radiation in the air is measured with scintillation style survey meter 1.5 meter above ground level (1.0 meter above ground level by May 5, 2011).

Measurement result

1. Radiation in the atmosphere

*Measurement is conducted in the morning in front of central gates in each container piers, and the average of the indicated two extreme values is recorded.

(Unit:μSv/h)

Area OiAomiShinagawaCentral Breakwater Reclaimed Land Remarks
Dec.28(Thu) 0.05 0.05 0.06 0.05
Dec.14(Thu) 0.05 0.05 0.05 0.05
Nov.30(Thu) 0.05 0.05 0.06 0.05
Nov.9(Thu) 0.05 0.03 0.05 0.05
Oct.26(Thu) 0.05 0.05 0.05 0.04
Oct.12(Thu) 0.04 0.04 0.04 0.04
Sep.28(Thu) 0.05 0.05 0.05 0.05
Sep.14(Thu) 0.05 0.05 0.04 0.04
Aug.31(Thu) 0.05 0.04 0.04 0.04
Aug.17(Thu) 0.04 0.04 0.03 0.04
Aug.3(Thu) 0.05 0.04 0.05 0.04
Jul.20(Thu) 0.05 0.05 0.05 0.04
Jul.6(Thu) 0.05 0.05 0.05 0.04
Jun.22(Thu) 0.05 0.04 0.04 0.04
Jun.8(Thu) 0.05 0.04 0.05 0.04
May.25(Thu) 0.05 0.04 0.05 0.05
May.11(Thu) 0.05 0.04 0.05 0.04
Apr.20(Thu) 0.05 0.03 0.06 0.04
Apr.6(Thu) 0.05 0.05 0.06 0.04
Mar.30(Thu) 0.05 0.05 0.04 0.05
Mar.23(Thu) 0.06 0.03 0.06 0.06
Mar.16(Thu) 0.04 0.04 0.04 0.04
Mar.9(Thu) 0.03 0.04 0.04 0.04
Mar.2(Thu) 0.05 0.05 0.05 0.05
Feb.23(Thu) 0.03 0.04 0.04 0.04
Feb.16(Thu) 0.04 0.04 0.04 0.05
Feb.9(Thu) 0.05 0.04 0.05 0.04
Feb.2(Thu) 0.03 0.04 0.04 0.04
Jan.26(Thu) 0.05 0.05 0.05 0.05
Jan.19(Thu) 0.05 0.05 0.05 0.05
Jan.12(Thu) 0.03 0.04 0.04 0.04
Jan.5(Thu) 0.05 0.04 0.04 0.05

2. Radioactivity in the seawater (surface)

*Seawater to measure is obtained at the point between Oi Container Wharf and Aomi Container Wharf in the morning.
*"ND" means that the data were blow thedetection limit (not detected).

(Unit:Bq/L)

Type Iodine-131Caesium-134 Caesium-137Remarks
Dec.28(Thu) ND ND ND
Dec.14(Thu) ND ND ND
Nov.30(Thu) ND ND ND
Nov.9(Thu) ND ND ND
Oct.26(Thu) ND ND ND
Oct.12(Thu) ND ND ND
Sep.28(Thu) ND ND ND
Sep.14(Thu) ND ND ND
Aug.31(Thu) ND ND ND
Aug.17(Thu) ND ND ND
Aug.3(Thu) ND ND ND
Jul.20(Thu) ND ND ND
Jul.6(Thu) ND ND ND
Jun.22(Thu) ND ND ND
Jun.8(Thu) ND ND ND
May.25(Thu) ND ND ND
May.11(Thu) ND ND ND ※海水のみ5/12に測定
Apr.20(Thu) ND ND ND
Apr.6(Thu) ND ND ND
Mar.30(Thu) ND ND ND
Mar.23(Thu) ND ND ND
Mar.16(Thu) ND ND ND
Mar.9(Thu) ND ND ND
Mar.2(Thu) ND ND ND
Feb.23(Thu) ND ND ND ※海水のみ2/24に測定
Feb.16(Thu) ND ND ND
Feb.9(Thu) ND ND ND
Feb.2(Thu) ND ND ND
Jan.26(Thu) ND ND ND
Jan.19(Thu) ND ND ND
Jan.12(Thu) ND ND ND
Jan.5(Thu) ND ND ND

3.Radiation at container surfaces

*Measure radiation dose on the surface of each sample container at the gate of pier head, and disclose number of samples, maximum volume, minimum volume, average volume by pier.

(Unit: pcs,μSv/h)

Area Oi Aomi Shinagawa Central Breakwater Reclaimed Land
Dec.28(Thu) samples 20 15 5 5
maximum 0.04 0.05 0.05 0.04
minimum 0.02 0.02 0.02 0.02
average 0.03 0.03 0.03 0.03
decontaminated 0 0 0 0
Dec.14(Thu) samples 23 15 0 6
maximum 0.05 0.04 0.04
minimum 0.02 0.02 0.02
average 0.03 0.03 0.03
decontaminated 0 0 0
Nov.30(Thu) samples 35 18 4 10
maximum 0.05 0.05 0.04 0.05
minimum 0.02 0.02 0.03 0.02
average 0.03 0.03 0.04 0.03
decontaminated 0 0 0 0
Nov.9(Thu) samples 27 13 2 7
maximum 0.05 0.04 0.03 0.04
minimum 0.01 0.01 0.02 0.02
average 0.03 0.03 0.03 0.03
decontaminated 0 0 0 0
Oct.26(Thu) samples 35 16 3 7
maximum 0.05 0.04 0.04 0.04
minimum 0.02 0.02 0.03 0.03
average 0.03 0.03 0.04 0.04
decontaminated 0 0 0 0
Oct.12(Thu) samples 25 14 4 6
maximum 0.04 0.04 0.04 0.04
minimum 0.03 0.02 0.03 0.03
average 0.03 0.03 0.04 0.03
decontaminated 0 0 0 0
Sep.28(Thu) samples 35 16 8 7
maximum 0.05 0.1 0.05 0.04
minimum 0.02 0.02 0.02 0.03
average 0.04 0.03 0.03 0.04
decontaminated 0 0 0 0
Sep.14(Thu) samples 27 19 2 7
maximum 0.05 0.05 0.04 0.03
minimum 0.02 0.02 0.02 0.02
average 0.03 0.03 0.03 0.03
decontaminated 0 0 0 0
Aug.31(Thu) samples 26 13 5 7
maximum 0.05 0.04 0.05 0.04
minimum 0.01 0.01 0.02 0.02
average 0.03 0.02 0.03 0.03
decontaminated 0 0 0 0
Aug.17(Thu) samples 21 9 0 6
maximum 0.04 0.04 0.04
minimum 0.03 0.03 0.03
average 0.03 0.03 0.04
decontaminated 0 0 0
Aug.3(Thu) samples 27 16 3 7
maximum 0.04 0.03 0.03 0.04
minimum 0.01 0.01 0.02 0.02
average 0.03 0.02 0.03 0.03
decontaminated 0 0 0 0
Jul.20(Thu) samples 30 14 5 7
maximum 0.05 0.04 0.04 0.05
minimum 0.02 0.02 0.03 0.02
average 0.03 0.03 0.04 0.04
decontaminated 0 0 0 0
Jul.6(Thu) samples 25 15 7 7
maximum 0.05 0.04 0.04 0.04
minimum 0.02 0.02 0.02 0.02
average 0.03 0.03 0.03 0.03
decontaminated 0 0 0 0
Jun.22(Thu) samples 26 12 6 6
maximum 0.04 0.04 0.05 0.04
minimum 0.02 0.02 0.02 0.03
average 0.03 0.03 0.03 0.03
decontaminated 0 0 0 0
Jun.8(Thu) samples 27 15 6 8
maximum 0.04 0.03 0.05 0.05
minimum 0.02 0.01 0.02 0.02
average 0.03 0.02 0.03 0.04
decontaminated 0 0 0 0
May.25(Thu) samples 35 18 8 9
maximum 0.05 0.05 0.04 0.04
minimum 0.02 0.02 0.03 0.02
average 0.03 0.03 0.04 0.03
decontaminated 0 0 0 0
May.11(Thu) samples 26 18 1 9
maximum 0.04 0.04 0.04 0.04
minimum 0.01 0.01 0.03 0.02
average 0.03 0.02 0.04 0.03
decontaminated 0 0 0 0
Apr.20(Thu) samples 28 20 7 7
maximum 0.05 0.05 0.05 0.04
minimum 0.01 0.01 0.02 0.02
average 0.03 0.03 0.04 0.03
decontaminated 0 0 0 0
Apr.6(Thu) samples 27 10 7 6
maximum 0.04 0.04 0.05 0.04
minimum 0.01 0.01 0.01 0.02
average 0.03 0.02 0.03 0.03
decontaminated 0 0 0 0
Mar.30(Thu) samples 29 19 1 5
maximum 0.07 0.05 0.03 0.04
minimum 0.01 0.01 0.02 0.02
average 0.03 0.03 0.03 0.03
decontaminated 0 0 0 0
Mar.23(Thu) samples 23 14 6 5
maximum 0.04 0.03 0.04 0.04
minimum 0.01 0.01 0.02 0.02
average 0.03 0.02 0.03 0.03
decontaminated 0 0 0 0
Mar.16(Thu) samples 29 16 6 5
maximum 0.05 0.05 0.04 0.03
minimum 0.01 0.01 0.01 0.02
average 0.03 0.02 0.02 0.03
decontaminated 0 0 0 0
Mar.9(Thu) samples 22 11 5 6
maximum 0.04 0.04 0.04 0.04
minimum 0.02 0.02 0.03 0.03
average 0.03 0.03 0.03 0.03
decontaminated 0 0 0 0
Mar.2(Thu) samples 30 22 4 7
maximum 0.05 0.04 0.03 0.04
minimum 0.01 0.01 0.02 0.02
average 0.03 0.02 0.03 0.03
decontaminated 0 0 0 0
Feb.23(Thu) samples 25 14 5 6
maximum 0.04 0.04 0.04 0.04
minimum 0.02 0.02 0.03 0.03
average 0.03 0.03 0.04 0.04
decontaminated 0 0 0 0
Feb.16(Thu) samples 23 13 6 6
maximum 0.04 0.05 0.05 0.04
minimum 0.01 0.01 0.02 0.02
average 0.03 0.03 0.03 0.03
decontaminated 0 0 0 0
Feb.9(Thu) samples 23 13 4 6
maximum 0.04 0.04 0.04 0.04
minimum 0.02 0.02 0.02 0.02
average 0.03 0.03 0.03 0.03
decontaminated 0 0 0 0
Feb.2(Thu) samples 24 11 5 6
maximum 0.04 0.04 0.04 0.04
minimum 0.03 0.02 0.03 0.03
average 0.03 0.03 0.04 0.04
decontaminated 0 0 0 0
Jan.26(Thu) samples 25 15 5 6
maximum 0.05 0.04 0.04 0.04
minimum 0.01 0.01 0.02 0.02
average 0.03 0.02 0.03 0.03
decontaminated 0 0 0 0
Jan.19(Thu) samples 25 11 5 6
maximum 0.05 0.04 0.03 0.04
minimum 0.01 0.01 0.01 0.02
average 0.03 0.02 0.02 0.03
decontaminated 0 0 0 0
Jan.12(Thu) samples 23 15 5 6
maximum 0.04 0.04 0.04 0.04
minimum 0.02 0.03 0.03 0.03
average 0.03 0.03 0.04 0.03
decontaminated 0 0 0 0
Jan.5(Thu) samples 26 9 1 6
maximum 0.08 0.05 0.05 0.04
minimum 0.01 0.01 0.03 0.02
average 0.03 0.03 0.04 0.03
decontaminated 0 0 0 0

For inquiries about our business,
please contact us through the following:

Bureau of Port and Harbor,Tokyo Metropolitan Government

EMail:kouwan_kouhou@section.metro.tokyo.jp

8-1 Nishishinjuku 2-chome Shinjuku-ku Tokyo 163-8001, Japan