Daiki NAGAI

A Study on the Influence of Risk Perception on Residents’ Behavior during a Nuclear Disaster

Kazushi SANO

This study aims to clarify the factors influencing residents’ decision-making during nuclear disasters. Following the accident at the Fukushima Daiichi Nuclear Power Plant, Japan established Nuclear Emergency Planning Zones consisting of the Precautionary Action Zone (PAZ) and the Urgent Protective Action Planning Zone (UPZ). Since then, local governments have developed evacuation plans, conducted disaster preparedness drills, and implemented awareness programs for residents. However, nuclear disasters occur infrequently and their impacts are difficult to perceive directly through human senses. Consequently, residents’ interest and understanding tend to remain limited, and their actual behavior during emergencies may differ from what authorities assume in official disaster plans. In particular, in UPZ areas, both sheltering indoors and evacuation are possible protective actions. This situation may lead to voluntary evacuation caused by anxiety or misunderstanding, which could generate secondary problems such as traffic congestion and increased radiation exposure risk. Therefore, it is important to clarify how residents form perceptions and make behavioral decisions in nuclear emergency situations.
In this study, interviews with local governments and a questionnaire survey of residents in PAZ and UPZ areas in Niigata Prefecture were conducted. The relationships among knowledge, communication, risk perception, disaster preparedness behavior, and actions during disasters were examined using structural equation modeling (SEM). The analysis focused on how these factors interact with each other and influence behavioral decisions, with knowledge positioned as the starting point of the decision-making structure.
The results indicate that increased knowledge among residents functions as the starting point of behavioral decision-making. Residents with greater understanding of nuclear emergency systems, basic radiation knowledge, and the effectiveness of sheltering indoors tend to communicate more actively with family members and neighbors about disaster preparedness. Increased communication reduces excessive anxiety and fear related to nuclear disasters. As risk perception becomes moderated, residents are less likely to evacuate immediately and are more likely to select appropriate actions, such as sheltering indoors depending on the situation. These findings suggest that improving residents’ disaster responses requires the promotion of accurate and systematic knowledge.