Shelter-in-place (SIP) is positioned alongside evacuation as a primary protective action during nuclear emergencies in Japan. However, despite the progressive development of institutional systems and guidelines, limited attention has been paid to the practical implementation of SIP in medical institutions. In particular, hospitals that must continue to provide care for the elderly, critically ill, and other non-evacuable inpatients lack integrated operational models that address business continuity planning (BCP), radiation protection, staff mobilisation, zoning, and the real-world operation of positive-pressure systems. Against this background, since the fiscal year 2024, a working group on nuclear disaster preparedness has been established at Japanese Red Cross Matsue Hospital, a designated disaster base hospital located within the urgent protective action planning zone (UPZ) of the Shimane Nuclear Power Plant. This working group brings together multidisciplinary hospital departments and external stakeholders, including local governments, relevant service providers, and academic institutions, and operates under a permanent, multilayered governance structure. Through staged preparatory reviews within each department and integrated discussions at plenary meetings, operational challenges related to SIP were systematically identified and incorporated into hospitallevel BCP. This initiative represents Japan's first implementation-oriented effort to examine SIP not only as a conceptual or administrative measure but also as an operational strategy grounded in realworld hospital practice. By enhancing the feasibility of nuclear emergency preparedness in medical institutions located within UPZs, this study provides practical insights that may inform future policy development and be applicable to other regions.
Yamamoto et al. (Fri,) studied this question.