Citation

Iwai S, Sasaki M, Higaki S, Yamanishi H, Kai M. J. Radiol. Prot. 2019; ePub(ePub): ePub.

Affiliation

Department of Health Sciences, Oita University of Nursing and Health Sciences, Megusuno 2944-9, Oita, Oita, 870-1201, JAPAN.

Copyright

(Copyright © 2019, Institute of Physics Publishing)

DOI

10.1088/1361-6498/ab26e1

PMID

31163409

Abstract

This paper describes an overview of the radiation protection response to the plutonium intake accident that occurred at the Plutonium Fuel Facility of the Oarai Research and Development Center of the Japan Atomic Energy Agency on June 6, 2017. In the hood of the analyzing room at the Plutonium Fuel Facility five workers were checking a storage container of fast reactor nuclear fuel material. Around 11:15 a.m., vinyl bags inside the fuel material container containing plutonium and enriched uranium burst during the inspection work. All the workers heard the bang, which caused misty dust leakage from the container. This event caused significant both skin and nasal α-contamination for three workers and just skin α-contamination for one worker. Decontamination was conducted in the shower room. Then the five workers were transferred to the Nuclear Fuel Cycle Engineering Laboratory to evaluate inhalation intake of plutonium etc. in the lungs. The maximum values of 2.2×10⁴ for ²³⁹Pu and 2.2×10² Bq for ²⁴¹Am were estimated by the lung monitor. Based on these results, injection of a chelate agent was conducted for prompt excretion of plutonium etc. The next morning, the five workers were transferred to the National Institute of Radiological Sciences for treatment including decontamination of their skin and measurement by a lung monitor. At that time no obvious energy peak was confirmed for plutonium. The Japan Health Physics Society launched an ad-hoc working group for plutonium intake accident around the middle of June to survey issues and to extract lessons for radiological protection. The authors, who are the members of the ad-hoc working group, will here report the activity of the working group.

© 2019 Society for Radiological Protection. Published on behalf of SRP by IOP Publishing Limited. All rights reserved.

Language: en

Keywords

JAEA Oarai; NIRS; Plutonium intake accident; chelating-agent administration; decontamination; lung monitor; skin