著者
河野 孝央
出版者
日本放射線安全管理学会
雑誌
日本放射線安全管理学会誌 (ISSN:13471503)
巻号頁・発行日
vol.9, no.2, pp.133-140, 2010 (Released:2011-12-20)
参考文献数
17
被引用文献数
4

Potassic chemical fertilizers contain potassium, a small part of which is potassium-40. Since potassium-40 is a naturally occurring radioisotope, potassic chemical fertilizers are often used for demonstrations of the existence of natural radioisotopes and radiation. To fabricate radiation sources as educational tools, the compression and formation method developed by our previous study was applied to 13 brands of commercially available chemical fertilizers containing different amounts of potassium. The suitability (size, weight, and solidness) of thus fabricated sources was examined and 12 of them were selected as easy-to-use radiation sources at radiation educational courses. The radiation strength (radiation count rate measured by a GM survey meter) and potassium content of the 12 sources were examined. It was found that the count rate was wholly proportional to the percentage of potassium, and a new educational application was proposed and discussed for understanding that the substance emitting radiation must be the potassium present in the raw fertilizers.
著者
三浦 美和 林田 りか 高尾 秀明 小野 孝二 松田 尚樹
出版者
Japanese Society of Radiation Safety Management
雑誌
日本放射線安全管理学会誌 (ISSN:13471503)
巻号頁・発行日
vol.12, no.1, pp.46-53, 2013

From October to December 2010, just before the radiological accident at the Tokyo Electric Power Company Fukushima Daiichi nuclear power plant, 71 radiation professionals belonging to the radiation facilities in Japan were asked what they consider as a "safe" dose of radiation for themselves, their spouse, parents, children, brothers and friends. Although the "safe" dose varied widely from less than 1 mSv/y to higher than 100 mSv/y, the average dose was 35.6 mSv/y that was around the middle point between the exposure dose limits for annual average (20 mSv/y) and for any single year (50 mSv/y). Similar results were obtained from another surveys for the members of Japan Radioisotope Association (36.9 mSv/y) and for the Oita Prefectural Hospital (36.8 mSv/y). Among the family members and friends, the minimum average "safe" dose was 8.5 mSv/y for children, to whom 50% of responders claimed the "safe" dose less than 1 mSv. Gender, age and specialty of the responder also affected the "safe" dose. These findings suggest that the perception of radiation risk varies widely and that the legal exposure dose limit derived from the regulatory science may act as an anchor of safety even in radiation professionals. The different level of risk perception for different target groups in radiation professionals appears similar to those in non-professional whole population. The gap between these characteristics of real radiation professionals and the generally accepted picture of radiation professionals might take a part in a state of confusion after the radiological accident.
著者
三浦 美和 林田 りか 高尾 秀明 小野 孝二 松田 尚樹
出版者
日本放射線安全管理学会
雑誌
日本放射線安全管理学会誌 (ISSN:13471503)
巻号頁・発行日
vol.12, no.1, pp.46-53, 2013 (Released:2013-07-26)
参考文献数
21

From October to December 2010, just before the radiological accident at the Tokyo Electric Power Company Fukushima Daiichi nuclear power plant, 71 radiation professionals belonging to the radiation facilities in Japan were asked what they consider as a “safe” dose of radiation for themselves, their spouse, parents, children, brothers and friends. Although the “safe” dose varied widely from less than 1 mSv/y to higher than 100 mSv/y, the average dose was 35.6 mSv/y that was around the middle point between the exposure dose limits for annual average (20 mSv/y) and for any single year (50 mSv/y). Similar results were obtained from another surveys for the members of Japan Radioisotope Association (36.9 mSv/y) and for the Oita Prefectural Hospital (36.8 mSv/y). Among the family members and friends, the minimum average “safe” dose was 8.5 mSv/y for children, to whom 50% of responders claimed the “safe” dose less than 1 mSv. Gender, age and specialty of the responder also affected the “safe” dose. These findings suggest that the perception of radiation risk varies widely and that the legal exposure dose limit derived from the regulatory science may act as an anchor of safety even in radiation professionals. The different level of risk perception for different target groups in radiation professionals appears similar to those in non-professional whole population. The gap between these characteristics of real radiation professionals and the generally accepted picture of radiation professionals might take a part in a state of confusion after the radiological accident.