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Hirouchi, Jun; Takahara, Shogo; Komagamine, Hiroshi*; Kato, Nobuyuki*; Matsui, Yasuto*; Yoneda, Minoru*
Journal of Radiological Protection, 41(3), p.S139 - S149, 2021/09
Times Cited Count:0 Percentile:0.01(Environmental Sciences)Sheltering is one of the countermeasures for protection against radiation exposures in nuclear accidents. The effectiveness of sheltering is often expressed by the reduction factor, that is the ratio of the indoor to the outdoor cumulative radioactivity concentrations or doses. The indoor concentration is mainly controlled by the air exchange rate, penetration factor, and indoor deposition rate. The penetration factor and indoor deposition rate depend on the surface and opening materials. We investigated experimentally these parameters of I and particles. The experiment was performed in two apartment houses, three single-family houses, and chambers. The obtained penetration factor ranged 0.3
1 for particles of 0.3
1
m and 0.15
0.7 for I
depending on the air exchange rate. The indoor deposition rate for a house room ranged 0.007
0.2 h
for particles of 0.3
1
m and 0.2
1.5 h
for I
depending on floor materials.
Hirouchi, Jun; Takahara, Shogo; Yoshimura, Kazuya
Journal of Environmental Radioactivity, 232, p.106572_1 - 106572_6, 2021/06
Times Cited Count:1 Percentile:65.97(Environmental Sciences)Information on the radioactivity distribution inside and outside houses is useful for indoor external dose assessments. In this study, we collected both soil samples around the target houses and house material samples (i.e., of the floor, inner wall, ceiling, outer wall, and roof). The radioactivity of the samples was measured using a high-purity germanium detector. The surface contamination densities of the floor, inner wall, ceiling, outer wall, and roof relative to the ground were 3 10
7
10
, 6
10
4
10
, 7
10
3
10
, 2
10
1
10
, and 4
10
2
10
, respectively. The relative surface contamination densities varied depending on the material, its location, and the orientation of the surface.
Hirouchi, Jun; Tokashiki, Yuji*; Takahara, Shogo; Manabe, Kentaro
JAEA-Research 2021-001, 284 Pages, 2021/03
Doses to the public are calculated with internal dose coefficients based on the publications of the International Commission on Radiological Protection (ICRP) in OSCAAR, which is a level 3 Probabilistic Risk Assessment code developed by Japan Atomic Energy Agency (JAEA). The gastrointestinal absorption fraction, , which is one of parameters of internal dose coefficient, is given the recommended value. However, although it has been reported that
has uncertainty, the uncertainty analysis of
has been performed on few radionuclides. In this report, to evaluate the influence of uncertainty of
on the internal dose, we calculated the internal dose coefficient with various
, and derive the relationship between the coefficient and
. As a result, we indicate that the relationships are expressed by a linear function for radionuclides with a half-life of more than 0.5 days and are expressed by a cubic function for radionuclides with a half-life of less than 0.5 days.
Yamada, Ryohei; Kono, Takahiko; Nakajima, Junya; Hirouchi, Jun; Tsuji, Tomoya; Umeda, Masayuki; Igarashi, Yu*; Koike, Hiromi*
Hoken Butsuri (Internet), 56(1), p.32 - 38, 2021/03
no abstracts in English
Futemma, Akira; Sanada, Yukihisa; Kawasaki, Yoshiharu*; Iwai, Takeyuki*; Hiraga, Shogo*; Sato, Kazuhiko*; Haginoya, Masashi*; Matsunaga, Yuki*; Kikuchi, Hikaru*; Ishizaki, Azusa; et al.
JAEA-Technology 2020-019, 128 Pages, 2021/02
A large amount of radioactive material was released by the nuclear disaster of Fukushima Daiichi Nuclear Power Station (FDNPS), Tokyo Electric Power Company, caused by the Great East Japan Earthquake and the following tsunami on March 11, 2011. After the nuclear disaster, airborne radiation monitoring using manned helicopter has been utilized to grasp rapidly and widely the distribution of the radioactive materials around FDNPS. We prepare the data of background radiation dose, geomorphic characteristics and the controlled airspace around nuclear facilities of the whole country in order to make effective use of the monitoring technique as a way of emergency radiation monitoring and supply the results during accidents of the facilities. Furthermore, the airborne radiation monitoring has been conducted in Integrated Nuclear Emergency Response Drill to increase effectiveness of the monitoring. This report is summarized that the knowledge as noted above achieved by the aerial radiation monitoring around Higashidori nuclear power station, the nuclear fuel reprocessing plant in Rokkasho village and Shika nuclear power station, the full details of the aerial radiation monitoring in Integrated Nuclear Emergency Response Drill in the fiscal 2019. In addition, examination's progress aimed at introduction of airborne radiation monitoring using unmanned helicopter during nuclear disaster and the technical issues are summarized in this report.
Futemma, Akira; Sanada, Yukihisa; Ishizaki, Azusa; Kawasaki, Yoshiharu*; Iwai, Takeyuki*; Hiraga, Shogo*; Sato, Kazuhiko*; Haginoya, Masashi*; Matsunaga, Yuki*; Kikuchi, Hikaru*; et al.
JAEA-Technology 2020-018, 121 Pages, 2021/02
By the nuclear disaster of Fukushima Daiichi Nuclear Power Station (FDNPS), Tokyo Electric Power Company (TEPCO), caused by the Great East Japan Earthquake and the following tsunami on March 11, 2011, a large amount of radioactive material was released from the FDNPS. After the nuclear disaster, airborne radiation monitoring using manned helicopter has been conducted around FDNPS. The results in the fiscal 2019 were summarized in this report. Analysis taken topographical effects into consideration was applied to the result of airborne monitoring to improve the precision of conventional method. In addition, discrimination method of gamma rays from Rn-progenies was also utilized to evaluate their effect on aerial radiation monitoring.
Hirouchi, Jun; Tani, Kotaro*; Tamakuma, Yuki*; Nakasone, Shunya*; Koike, Hiromi*
Hoken Butsuri (Internet), 55(4), p.185 - 190, 2020/12
no abstracts in English
Futemma, Akira; Sanada, Yukihisa; Komiya, Tomokazu; Iwai, Takeyuki*; Seguchi, Eisaku*; Matsunaga, Yuki*; Kawabata, Tomoki*; Haginoya, Masashi*; Hiraga, Shogo*; Sato, Kazuhiko*; et al.
JAEA-Technology 2019-017, 95 Pages, 2019/11
By the nuclear disaster of Fukushima Daiichi Nuclear Power Station (FDNPS), Tokyo Electric Power Company (TEPCO), caused by the Great East Japan Earthquake and the following tsunami on March 11, 2011, a large amount of radioactive material was released from the FDNPS. After the nuclear disaster, airborne radiation monitoring using manned helicopter was conducted around FDNPS. We have carried out the background radiation monitoring around the nuclear power stations of the whole country to apply the airborne radiation monitoring technique that has been cultivated in the aerial monitoring around FDNPS against nuclear emergency response. The results of monitoring around Shimane and Hamaoka Nuclear Power Stations in the fiscal 2018 were summarized in this report. In addition, technical issues were described.
Futemma, Akira; Sanada, Yukihisa; Ishizaki, Azusa; Komiya, Tomokazu; Iwai, Takeyuki*; Seguchi, Eisaku*; Matsunaga, Yuki*; Kawabata, Tomoki*; Haginoya, Masashi*; Hiraga, Shogo*; et al.
JAEA-Technology 2019-016, 116 Pages, 2019/11
By the nuclear disaster of Fukushima Daiichi Nuclear Power Station (FDNPS), Tokyo Electric Power Company (TEPCO), caused by the Great East Japan Earthquake and the following tsunami on March 11, 2011, a large amount of radioactive material was released from the FDNPS. After the nuclear disaster, airborne radiation monitoring using manned helicopter has been conducted around FDNPS. The results in the fiscal 2018 were summarized in this report. Discrimination method of gamma rays from Rn-progenies was also utilized to evaluate their effect on aerial radiation monitoring. In addition, analysis taken topographical effects into consideration was applied to previous results of airborne monitoring to improve the precision of conventional method.
Miwa, Kazuji; Terasaka, Yuta; Ochi, Kotaro; Futemma, Akira; Sasaki, Miyuki; Hirouchi, Jun
Nihon Genshiryoku Gakkai-Shi ATOMO, 61(9), p.687 - 691, 2019/09
This report summarizes the contents of the session of the Health Physics and Environment Science Division, which was held in Atomic Energy Society of Japan 2019 Spring Meeting. In this session, six students and young researchers who engaged in the field of nuclear energy and radiation gave a lecture about health physics and environmental science research through their expertise. After the all presentations end, we took discussion time about the issues and future development in this field with all attendees. In this report, we summarized each lecture outline and discussion contents.
Hirouchi, Jun; Takahara, Shogo; Komagamine, Hiroshi*; Munakata, Masahiro
Proceedings of Asian Symposium on Risk Assessment and Management 2019 (ASRAM 2019) (USB Flash Drive), 7 Pages, 2019/09
no abstracts in English
Futemma, Akira; Sanada, Yukihisa; Iwai, Takeyuki*; Seguchi, Eisaku; Matsunaga, Yuki*; Kawabata, Tomoki; Toyoda, Masayuki*; Tobita, Shinichiro*; Hiraga, Shogo*; Sato, Kazuhiko*; et al.
JAEA-Technology 2018-016, 98 Pages, 2019/02
By the nuclear disaster of Fukushima Daiichi Nuclear Power Station (FDNPS), Tokyo Electric Power Company (TEPCO), caused by the Great East Japan Earthquake and the following tsunami on March 11, 2011, a large amount of radioactive material was released from the NPS. After the nuclear disaster, airborne radiation monitoring using manned helicopter was conducted around FDNPS. We have carried out the background monitoring around the nuclear power stations of the whole country to apply the airborne radiation monitoring technique that has been cultivated in Fukushima against nuclear emergency response. The results of monitoring around Tomari, Kashiwazaki-Kariwa and Genkai Nuclear Power Station in the fiscal 2017 were summarized in this report. In addition, technical issues were described.
Futemma, Akira; Sanada, Yukihisa; Ishizaki, Azusa; Iwai, Takeyuki*; Seguchi, Eisaku; Matsunaga, Yuki*; Kawabata, Tomoki; Toyoda, Masayuki*; Tobita, Shinichiro*; Hiraga, Shogo*; et al.
JAEA-Technology 2018-015, 120 Pages, 2019/02
By the nuclear disaster of Fukushima Daiichi Nuclear Power Station (FDNPS), Tokyo Electric Power Company (TEPCO), caused by the Great East Japan Earthquake and the following tsunami on March 11, 2011, a large amount of radioactive material was released from the NPS. After the nuclear disaster, airborne radiation monitoring using manned helicopter was conducted around FDNPS. The results in the fiscal 2017 were summarized in this report. In addition, we developed and systemized the discrimination technique of the Rn-progenies. The accuracy of aerial radiation monitoring was evaluated by taking into consideration GPS data error.
Hirouchi, Jun; Nishizawa, Yukiyasu*; Urabe, Yoshimi*; Shimada, Kazumasa; Sanada, Yukihisa; Munakata, Masahiro
Applied Radiation and Isotopes, 141, p.122 - 129, 2018/11
Times Cited Count:1 Percentile:17.98(Chemistry, Inorganic & Nuclear)Hirouchi, Jun; Takahara, Shogo; Komagamine, Hiroshi*; Munakata, Masahiro
Proceedings of Asian Symposium on Risk Assessment and Management 2018 (ASRAM 2018) (USB Flash Drive), 8 Pages, 2018/10
no abstracts in English
Sanada, Yukihisa; Mori, Airi; Iwai, Takeyuki; Seguchi, Eisaku; Matsunaga, Yuki*; Kawabata, Tomoki; Toyoda, Masayuki*; Tobita, Shinichiro*; Hiraga, Shogo; Sato, Yoshiharu; et al.
JAEA-Technology 2017-035, 69 Pages, 2018/02
By the nuclear disaster of Fukushima Daiichi Nuclear Power Station (FDNPS), Tokyo Electric Power Company (TEPCO), caused by the East Japan earthquake and the following tsunami occurred on March 11, 2011, a large amount of radioactive materials was released from the NPS. After the nuclear disaster, airborne radiation monitoring using manned helicopter was conducted around FDNPS. We carried out the background monitoring around the nuclear power stations of the whole country to apply a technique of the airborne radiation monitoring that is cultivated in Fukushima as a technology of nuclear emergency response. This result of the aerial radiation monitoring using the manned helicopter around Ooi, Takahama and Ikata Nuclear Power Station and in the fiscal 2016 were summarized in the report. In addition, technical issues were described.
Sanada, Yukihisa; Mori, Airi; Iwai, Takeyuki; Seguchi, Eisaku; Matsunaga, Yuki*; Kawabata, Tomoki; Toyoda, Masayuki*; Tobita, Shinichiro*; Hiraga, Shogo; Sato, Yoshiharu; et al.
JAEA-Technology 2017-034, 117 Pages, 2018/02
By the nuclear disaster of Fukushima Daiichi Nuclear Power Station (FDNPS), Tokyo Electric Power Company (TEPCO), caused by the East Japan earthquake and the following tsunami occurred on March 11, 2011, a large amount of radioactive materials was released from the NPS. After the nuclear disaster, airborne radiation monitoring using manned helicopter was conducted around FDNPS. This result of the aerial radiation monitoring using the manned helicopter in the fiscal 2016 were summarized in the report. In addition, we developed the discrimination technique of the Rn-progenies. The accuracy of aerial radiation monitoring was evaluated by taking into consideration GPS position error.
Takahara, Shogo; Watanabe, Masatoshi*; Hirouchi, Jun; Iijima, Masashi*; Munakata, Masahiro
Health Physics, 114(1), p.64 - 72, 2018/01
Times Cited Count:1 Percentile:17.98(Environmental Sciences)Hirouchi, Jun; Takahara, Shogo; Komagamine, Hiroshi*; Watanabe, Masatoshi*; Munakata, Masahiro
Proceedings of Asian Symposium on Risk Assessment and Management 2017 (ASRAM 2017) (USB Flash Drive), 11 Pages, 2017/11
no abstracts in English
Hirouchi, Jun; Takahara, Shogo; Iijima, Masashi; Watanabe, Masatoshi; Munakata, Masahiro
Radiation Physics and Chemistry, 140, p.127 - 131, 2017/11
Times Cited Count:2 Percentile:28.88(Chemistry, Physical)