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Kim, M.; Malins, A.*; Machida, Masahiko; Yoshimura, Kazuya; Saito, Kimiaki; Yoshida, Hiroko*
Nihon Genshiryoku Gakkai Wabun Rombunshi (Internet), 22(4), p.156 - 169, 2023/11
Dose reduction factor of a Japanese house is important information in the external exposure estimation of returning residents. In 2019, a total of 19 wooden houses were surveyed in Iitate Village and Namie Town using a gamma plotter that can continuously measure the air dose rate. In addition, the characteristics of the reduction factor were investigated from the measured air dose rate. In the vicinity of houses, uncontaminated areas exist underneath houses and, the ratio of paved surfaces such as asphalt roads is relatively high; furthermore, the pavement has a tendency for the radiation source to decay quickly. Therefore, the air dose rate near the house showed a relatively low value in common at all sites. Air dose rates above unpaved surfaces showed higher values and larger variations than those above paved surfaces within a radius of 50 m form the center of a house. The reduction factor was widely distributed even for one house, if the ratio of every air dose rate observed inside and outside the house is considered. It is suggested that a realistic reduction factor may not be obtained when the reduction factor is obtained based on the measured values at a small number of points that do not have the representativeness of the radiation field to be measured.
Abe, Tomohisa; Funaki, Hironori; Yoshimura, Kazuya; Shiribiki, Natsu*; Sanada, Yukihisa
JAEA-Data/Code 2023-001, 38 Pages, 2023/05
In this study, commissioned by the Cabinet Office, we conducted a survey on radioactive materials in atmospheric dust in three municipalities (Futaba Town, Okuma Town, and Tomioka Town) in Fukushima Prefecture to contribute to the assessment of internal exposure in the Specified Reconstruction and Revitalization Base (SRRB). Air dust samplers were installed in the targeted municipalities to investigate the atmospheric Cs concentrations and to evaluate internal exposure doses based on measured value. This report summarizes the results of measurements between 2018 and 2021. A database of information on internal exposure dose assessment results based on atmospheric radioactivity concentrations and actual measurements, and meteorological observation data was compiled.
Nugraha, E. D.*; Hosoda, Masahiro*; Kusdiana*; Untara*; Mellawati, J.*; Nurokhim*; Tamakuma, Yuki*; Ikram, A.*; Syaifudin, M.*; Yamada, Ryohei; et al.
Scientific Reports (Internet), 11(1), p.14578_1 - 14578_16, 2021/07
Times Cited Count:19 Percentile:84.25(Multidisciplinary Sciences)Mamuju is one of the regions in Indonesia which retains natural conditions but has relatively high exposure to natural radiation. The goals of the present study were to characterize exposure of the entire Mamuju region as a high natural background radiation area (HNBRA) and to assess the existing exposure as a means for radiation protection of the public and the environment. A cross-sectional study method was used with cluster sampling areas by measuring all parameters that contribute to external and internal radiation exposures. It was determined that Mamuju was a unique HNBRA with the annual effective dose between 17 and 115 mSv, with an average of 32 mSv. The lifetime cumulative dose calculation suggested that Mamuju residents could receive as much as 2.2 Sv on average which is much higher than the average dose of atomic bomb survivors for which risks of cancer and non-cancer diseases are demonstrated. The study results are new scientific data allowing better understanding of health effects related to chronic low-dose-rate radiation exposure and they can be used as the main input in a future epidemiology study.
Saito, Kimiaki; Takahara, Shogo; Uezu, Yasuhiro
Nihon Genshiryoku Gakkai-Shi ATOMO, 60(2), p.111 - 115, 2018/02
no abstracts in English
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
Saito, Kimiaki; Kurihara, Osamu*; Matsuda, Norihiro; Takahara, Shogo; Sato, Tetsuro*
Radioisotopes, 65(2), p.93 - 112, 2016/02
Late information is introduced on dose evaluation due to external exposures which employ an important role in the exposures due to the Fukushima accident. First, merits and demerits of the currently used two methods, that is the estimation based air dose rates and the measurements using personal dosimeters, are discussed indicating some basic data after a fundamental concept of external dose evaluation is provided. Next, main activities are summarized on external dose measurements and evaluations after the accident. Finally, a new trial on dose evaluation in introduced.
Saito, Kimiaki; Endo, Akira
Radioisotopes, 63(12), p.585 - 602, 2014/12
The article provides the fundamental information necessary for the appropriate evaluation of exposure doses in the environment. The basic characteristics of environmental rays from typical environmental sources are introduced; then, the dose conversion coeffcients for the public at different ages are summarized which were obtained from the simulation considering the basic characteristics of environmental rays. Further, the variations of environmental exposure doses due to a variety of factors, and the relation of exposure doses to measured air dose rates are discussed.
Saito, Kimiaki
Radioisotopes, 63(11), p.515 - 517, 2014/11
no abstracts in English
Sono, Hiroki; Kojima, Takuji; Soramasu, Noboru*; Takahashi, Fumiaki
JAERI-Conf 2005-007, p.315 - 320, 2005/08
Personal dosimeters provide a fundamental evaluation of external exposures to human bodies in radiation accidents. The dose distribution inside the body, which is needed to estimate the exposures from a result of personal dosimetry, has been evaluated mostly by computational simulations, while experimental data to verify the simulations are not sufficiently supplied, in particular, in criticality accident situations. For the purpose of obtaining the experimental data on external exposures inside the body, a preliminary experiment on criticality accident dosimetry was carried out at the Transient Experiment Critical Facility (TRACY) using a human phantom and tissue-equivalent dosimeters. The neutron and -ray absorbed doses inside the phantom could be satisfactorily measured by the combined use of an alanine dosimeter and a thermoluminescent dosimeter made of enriched lithium tetra borate. The doses measured in and on the phantom were regarded as reasonable in dose level and distribution by comparison with the doses measured in the free air.
Sono, Hiroki; Yanagisawa, Hiroshi*; Ono, Akio*; Kojima, Takuji; Soramasu, Noboru*
Journal of Nuclear Science and Technology, 42(8), p.678 - 687, 2005/08
Times Cited Count:4 Percentile:30.51(Nuclear Science & Technology)Component analysis of -ray doses in criticality accident situations is indispensable for further understanding on emission behavior of -rays and accurate evaluation of external exposure to human bodies. Such dose components were evaluated, categorizing -rays into four components: prompt, delayed, pseudo components in the period of criticality, and a residual component in the period after the termination of criticality. This evaluation was performed by the combination of dosimetry experiments at the TRACY facility using a thermoluminescent dosimeter (TLD) made of lithium tetra borate and computational analyses using a Monte Carlo code. The evaluation confirmed that the dose proportions of the above components varied with the distance from the TRACY core tank. This variation was due to the difference in attenuation of the individual components with the distance from the core tank. The evaluated dose proportions quantitatively clarified the contribution of the pseudo and the residual components to be excluded for accurate evaluation of -ray exposure.
Kawai, Katsuo; Endo, Akira; Noguchi, Hiroshi
JAERI-Data/Code 2002-013, 66 Pages, 2002/05
Effective dose coefficients by inhalation and ingestion have been calculated for 334 nuclides, including (1) nuclides with half-lives 10min and their daughters that are not listed in ICRP Publications and (2) nuclides with half-lives 10min that are produced in a spallation target. Dose calculation was carried out using a nuclear decay database DECDC and a decay data library newly compiled from the ENSDF. The dose coefficients were calculated with the computer code DOCAP based on the respiratory tract model and biokinetic model of ICRP. The calculated results are presented as tables, which are the same forms as those in ICRP Publs.68 and 72. The complete listings of the dose coefficients are arranged on a CD-ROM, DoseCD, as indexed tables for inhalation of ten particle sizes, ingestion and injection into blood for workers and members of the public. The dose coefficients calculated in the present study are useful to calculate internal doses for a variety of radionuclides produced in high energy proton accelerator facilities.
Endo, Akira; Yamaguchi, Yasuhiro
JAERI-Data/Code 99-047, p.24 - 0, 1999/12
no abstracts in English
Homma, Toshimitsu; Togawa, Orihiko
JAERI-Data/Code 96-034, 47 Pages, 1996/11
no abstracts in English
; ; Onodera, Junichi; ; Ikezawa, Yoshio
Proc. of the Int. Conf. on Radiation Effects and Protection, p.434 - 439, 1992/00
no abstracts in English
Radiat.Prot.Dosim., 18(4), p.221 - 228, 1987/04
Times Cited Count:7 Percentile:60.01(Environmental Sciences)no abstracts in English
Radiat.Prot.Dosim., 18(2), p.81 - 87, 1987/02
Times Cited Count:5 Percentile:50.76(Environmental Sciences)no abstracts in English
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Genshiryoku Kogyo, 32(9), p.70 - 74, 1986/09
no abstracts in English
Nuclear Instruments and Methods, 205, p.517 - 524, 1983/00
no abstracts in English
*;
JAERI-M 82-191, 72 Pages, 1982/12
no abstracts in English
; ; ; ;
JAERI-M 82-021, 292 Pages, 1982/03
no abstracts in English