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Nakagawa, Masahiro; Nojima, Shun; Fujii, Katsutoshi; Shishido, Nobuhito; Sakai, Toshiya; Umehara, Takashi; Shimizu, Isamu
Hoken Butsuri, 47(3), p.189 - 193, 2012/10
It is essential to wear an air-purifying respirator in the radiation works in a contaminated atmosphere. A breath-responsive-powered air-purifying respirator (BR-PAPR) has been recently developed. However, no research has yet been conducted to determine the protection factor (PF) of the BR-PAPR in actual workplaces. In this study, the PFs of the BR-PAPR were measured by a man-test apparatus and compared with those of a non-powered full face mask. The PFs were measured under three different situations; normal wearing condition, clogging the filter and leaving a gap between the face and the mask. Under these situations, it was found that the PFs of the BR-PAPR are higher than those of the non-powered full face mask. PFs greater than 4000 were obtained for 95% of the subjects who wear the BR-PAPR, and PFs over 6667, the upper limit of the man-test apparatus, were obtained for 49% of them. The questionnaire survey was conducted for workers. The results showed that the workers feel a reduced burden when they wear the BR-PAPR. The results of this study showed high protection performance and operation efficiency of the BR-PAPR.
Umehara, Takashi; Tayama, Toru; Akiyama, Isamu; Nagata, Yasushi*; Onodera, Satoru*
JAERI-Review 2004-019, 109 Pages, 2004/08
JAERI-Review-2004-019.pdf:10.84MB
This report has been written about the outline of the JT-60 related facility, the JT-60 gaseous waste treatment facility, radiation control equipments and a fundamental radiation control form, which are needed to carry out a radiation control by radiation control officer in Naka Fusion Research Establishment. Further, the following items has been arranged to tables; the low and in-house rules of a radiation protection to apply for the JT-60 facilities, specifications of the JT-60, main parameters and performance of the JT-60, a radiation generated by the JT-60 plasma discharge test, an permitted amount of radiation source and nuclear fuel, each performance of the radiation generators, specifications of the air exhaust facility and the radiation control facility. In addition, figures of the control area, system diagrams of the gaseous waste treatment facility and radiation control monitors are attached.
Furutani, Misa; Aoyagi, Hiroyuki*; Shirato, Yoshihiro; Nojima, Shun; Nakagawa, Masahiro; Otsuka, Yoshikazu; Niinuma, Shinichi*; Sakai, Toshiya; Muto, Yasushi; Nanri, Tomohiro; et al.
no journal, ,
no abstracts in English
Nakagawa, Masahiro; Nojima, Shun; Fujii, Katsutoshi; Shishido, Nobuhito; Sakai, Toshiya; Umehara, Takashi; Shimizu, Isamu
no journal, ,
no abstracts in English
Takahashi, Teruhiko; Niinuma, Shinichi; Futagawa, Kazuo; Otsuka, Yoshikazu; Muto, Yasushi; Sakai, Toshiya; Umehara, Takashi; Shimizu, Isamu; Umino, Takaaki; Yamada, Satoshi; et al.
no journal, ,
no abstracts in English
Kikuchi, Masamitsu; Umehara, Takashi; Shishido, Nobuhito; Kuramochi, Akihiko; Fujii, Katsutoshi; Nakajima, Junya
no journal, ,
no abstracts in English
Nakajima, Junya; Yokosuka, Yoshiyuki; Arakawa, Yuto; Shimizu, Isamu; Umehara, Takashi
no journal, ,
In NUCEF we monitor the radiation level continuously with 81 radiation monitors. Although these monitors are checked periodically, failures have occurred due to various reasons. Then we accumulated all monitor failures which had happened in recent 18 years, and categorized them by reason. This allowed us to find that the number of the failure much differs from monitor to monitor, and that there was a deviation between the reasons of the failure. After that, about degradation of GM tube used as dust monitor, which is by far the most of all reasons, we investigated the relation between the average cps and the interval of exchange. As a result, we couldn't find any causal relationship between the both. On the other hand, to improve the failure situation, we have exchanged expendables periodically, and furthermore, the result of the failure analysis should be fed back for better preventive maintenance.
Nakagawa, Masahiro; Kato, Takuya; Nojima, Shun; Sakai, Toshiya; Shishido, Nobuhito; Umehara, Takashi
no journal, ,
Mask fitting tester "MT-03" is widespread as educational equipment in medical institution and industrial organization. However, there are few examples introduced in order to check the protection performance of purifying respirators in nuclear facilities. In this study, we compared protection factors obtained by MT-03 and those obtained by Mask-man test apparatus "MT-100N". As a result, although the change of measurement result is larger and measured value is higher than that of MT-100N, it was found that protection performance can be checked appropriately.
Onuma, Isamu; Kobayashi, Makoto; Umehara, Takashi; Shimizu, Isamu
no journal, ,
no abstracts in English
Arakawa, Yuto; Fujii, Katsutoshi; Mimura, Ryuji; Nakashio, Nobuyuki; Onuma, Isamu; Shishido, Nobuhito; Umehara, Takashi
no journal, ,
no abstracts in English
Nojima, Shun; Sakai, Jun; Nakagawa, Masahiro; Shirato, Yoshihiro; Aoyagi, Hiroyuki; Otsuka, Yoshikazu; Sakai, Toshiya; Shishido, Nobuhito; Umehara, Takashi
no journal, ,
no abstracts in English
