Levels of radioactive materials in the fallout obtained everyday, 2024 Fiscal year

The sampling and measurement are conducted at the Tokyo Metropolitan Institute of Public Health (Hyakunin-cho, Shinjuku-ku, Tokyo)

Sampling date 131I
Bq/kg
Radioactive Cesium
134Cs
Bq/kg
137Cs
Bq/kg
9:30, Thu., 18 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Wed., 17 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Tue., 16 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Mon., 15 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Sun., 14 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Sat., 13 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Fri., 12 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Thu., 11 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Wed., 10 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Tue., 09 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Mon., 08 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Sun., 07 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Sat., 06 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Fri., 05 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Thu., 04 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Wed., 03 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Tue., 02 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Mon., 01 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
  • Samples are collected and analyzed everyday using a germanium semiconductor detector.
  • It is known that rainfall may increase values.
  • The number of significant digits of values is set as 2 in order to be consistent with that of the Japanese government.
  • Please see here about the principle behind “ND (Not Detectable)”.
  • A unit of values is Bq/m2, identical to MBq/km2.

Please see the pages for each year for data from previous surveys