Sixty-five years since born in Hiroshima and thirty-five years since involved in radiation dosimetry for Hiroshima/Nagasaki

History of radiation dosimetry for the Hiroshima-Nagasaki atomic bomb was briefly reviewed from the early radiation survey by Japanese scientists that began just several days after the bombing to the elaboration of DS02. External exposure of 23.7 mGy was estimated for the author's mother as an early entrant in Hiroshima. (author)