Radiation dose in park
About park in the city, we measure radiation dose of park.
1 general space radiation dose (a)
In central place one spot of use of park including open space of each park, we measure space γ (gamma) dose of radioactivity of surface of the earth 50cm (and sometimes 1m).
Radiation dose (b) at point that may become 2 Mike Rothe pots
Among facilities in park, we measure γ (gamma) dose of radioactivity of surface of the earth 1cm and 50cm based on the use situation of child at place that may become Mike Rothe pot.
[example of measurement point]
・The playground equipment outskirts (bottoms of landing of playground equipment compound under sandbox, exit, swing of slide)
・Places where rainwater is easy to collect on rainwater Masu on gutter
●Publication of result of a measurement
Result of a measurement divides into radiation dose (b) at point that may become general space radiation dose (a) and Mike Rothe pot in park and adds up.
Every ward, we equal a i u e o order in address.
|The ward name||General space radiation dose|
|It becomes Mike Rothe pot|
Radiation dose (b) at point with possibility
|Tsurumi||Result indication||Result indication|
|Kanagawa||Result indication||Result indication|
|The west||Result indication||Result indication|
|Medium||Result indication||Result indication|
|The south||Result indication||Result indication|
|Konan||Result indication||Result indication|
|Hodogaya||Result indication||Result indication|
|Asahi||Result indication||Result indication|
|Isogo||Result indication||Result indication|
|Kanazawa||Result indication||Result indication|
|Kohoku||Result indication||Result indication|
|Green||Result indication||Result indication|
|Green leaves||Result indication||Result indication|
|Tsuzuki||Result indication||Result indication|
|Tozuka||Result indication||Result indication|
|Honor||Result indication||Result indication|
|Spring||Result indication||Result indication|
|Seya||Result indication||Result indication|
Adobe Reader which Adobe Systems Incorporated (Adobe Systems Incorporated) distributes for free is necessary so that you see PDF file. You download one that you do not have from web site of the company, and please use after completing installation.
●About "indication" of correspondence of radiation dose result of a measurement in Yokohama-shi
|Higher surface of the earth||Yokohama-shi|
|1m||We cope using 0.23μSv/h or more as an indication|
|(50cm)||(we cope using 0.23μSv/h or more as an indication)
(when it is more than 0.23μSv/h, we measure even 1m)
|1cm||We cope using 0.59μSv/h or more as an indication|
●About measuring instrument
Measuring instrument which we used for the measurement has following four kinds.
Generally, measurements of GM counter become higher than scintillation detector.
This depends on difference in mechanism of apparatus, and scintillation detector is sensitive to radiation of constant direction, and measurements tend to appear highly because GM counter is sensitive to lateral radiation dose.
A: TCS-172B (product made in Hitachi Aloka Medical Corporation)
Detector NaI(TI) scintillation detector
B: Mr.Ganma A2700 type (product made in clear pulse company)
Detector CsI(TI) scintillation detector
C: PA -1000 Radi (product made in HORIBA Corporation)
Detector CsI(TI) scintillation detector
D: RDS -30 (product made in million technology company)
Detector energy compensation type GM counter
●Press release documents about radiation of park
Look at press release documents about radiation in park from this.
About result of a measurement of place (so-called Mike Rothe pot) where radiation dose of price that was higher than the [press release] outskirts was measured on September 29, 2011 <new Tsurumi Park>
About result of a measurement of place (so-called Mike Rothe pot) where radiation dose of price that was higher than the [press release] outskirts was measured on November 28, 2011 <Yahata, Tomioka Park>
(as for the inquiry)
City of Yokohama, Environmental Planning Bureau greenery maintenance section
Telephone: 045-671-3848 FAX: 045-664-2588
(reception hours: for from Monday to Friday for from 8:45 to 17:15)