Radiation dose measurement status at water purification plants

Measurement results of spatial radiation dose at water purification plants in Water Works Bureau are shown below.
Since September 2011, we have been measuring spatial radiation doses at the Yokohama Water Supply Memorial Hall and water purification plants visited by customers for tours, etc. Since 10 years have passed since the earthquake, the measurement of spatial radiation dose at water purification plants and other facilities has been completed with the measurement in April 2021.

Measure the position of 1cm and 50cm from the ground, respectively.

[Estimation of Response in Yokohama City]
・1 cm from the ground surface ：0.59μSv/h
・50cm from the ground surface: 0.23μSv/h

Yokohama Water Works Memorial Hall, Nishiya Water Purification Plant, Kawai Purification Plant, Kosuzume Purifiction Plant, Aoyama Water Source Office

※Measurements from April 2015 to April 2021 were made at 23 locations in 5 facilities.
※Measurements in October 2014 were made at 24 locations in 5 facilities.
※Measurements from September 2013 to April 2014 were 25 locations at 5 facilities.
※Measurements from May 2012 to August 2013 were 23 locations at 5 facilities.
※Measurements from March to April 2012 were made at 83 locations at 5 facilities.
※Measurements from November 2011 to February 2012 were 94 locations at 5 facilities.
※The measurement in September 2011 was 139 locations in 5 facilities and 7 reservoirs.

Environmental radiation monitor Radi (PA-1000) (CsI (TI) scintillation detector) (manufactured by HORIBA, Ltd.)
※The measurement in September 2011 uses the NaI(TI) scintillation detector TCS-172B (manufactured by Hitachi Aloka Medical).