@misc{oai:repo.qst.go.jp:00059855,
 author = {Fujimoto, Kenzo and 藤元 憲三},
 month = {Jul},
 note = {Relatively high dose to the lung due to radon and its progeny in the normal natural environment was recognized a few decades ago. However, the dose had not been paid much attention since its dose was localized only in the lung. In late seventies radon became worldwide concern due to the introduction of the dose unit of effective dose equivalent (effective dose in present terminology) by ICRP Publ. 26. In the early eighties UNSCEAR requested every member states to carry out nation-wide indoor radon survey for the population dose estimation in the world. Only limited number of countries at that time had completed the nation-wide indoor radon survey, such as Canada. In accordance with the UNSCEAR's request a radon survey was conducted by our group in Japan during 1985 and 1991. A robust, non-expensive and reliable passive detector was searched for the use of our nation-wide survey. Karlsruhe type passive radon detector was then chosen for the survey. The detector film was polycarbonate and its treatment after the exposure was the electrochemical etching. Using this method more than 7,000 houses throughout Japan were measured to obtain annual average indoor radon concentration. The survey demonstrated that the percentage of houses having high radon concentration more than 150 Bq m-3 was only 0.4% of the house stock in Japan. We additionally found Karlsruhe type passive radon detector had higher air exchange rate than expected and showed radon concentrations affected by thoron. To solve the interference of thoron in radon measurement a new passive detector (UFO type) was designed to discriminate radon from thoron. The second nation-wide survey using the UFO type detector was conducted during 1992 and 1996 with a relatively small scale. After the finalization of our indoor radon surveys, all our devices related to the passive radon measurements were donated to Vinca in November 2002 wishing the active usage of the tools in this region., Promotion of New Electrochemical Etching Facility and Its Applications to Natural Radiation Studies in Western Balkan Countries},
 title = {Introduction of Electrochemical Etching Devices in VINCA},
 year = {2003}
}