Radiation protection guidelines for releasing commodities from radiation controlled areas

管理区域からの物品搬出に関する放射線防護ガイドライン

山本 英明

Yamamoto, Hideaki

管理区域からの物品の持出に対する管理は、物品の表面汚染密度に対して設定された基準値に基づいて行われている。現行基準値は約40年前に、当時の放射線防護上の知見に基づいて導出された。日本保健物理学会放射線防護標準化委員会では、物品持出にかかわる放射線防護の実態調査結果に基づき、表面汚染に関する防護規準改訂の検討を進めている。本報告では、検討にあたっての論点,検討の状況と方向性等を説明する。

The Japanese radiation protection criteria for releasing commodities from radiation controlled areas are set in terms of the radioactive contamination concentrations on the surface of the commodities. The current criteria were established more than 40 years ago, based on the knowledge of radiological protection of those days. The Japanese Standardization Committee on Radiation Protection, Japan Health Physics Society has been making some fact-finding studies on the control practices for releasing commodities from radiation controlled areas in some typical nuclear sites. Based on the results from these studies the Committee will develop a new approach to a possible amendment of the release criteria. The current principles of radiological protection suggest that an application of the concept of "clearance of materials from regulatory control" may establish a logical and practical framework for radiological protection for releasing commodities from radiation controlled areas.