Disasters are defined as complex processes arising from the interaction of hazard, exposure, and vulnerability, disrupting the physical, economic, and social structure of society beyond its existing coping capacity. At the international level, an event is generally classified as a “disaster” when at least one of the following criteria is met: the death of at least 10 individuals, the impact on 100 or more people, the declaration of a state of emergency, or an international appeal for assistance. Disasters are broadly categorized into natural disasters, including geological, meteorological, biological, and space-related events; technological or human-induced disasters, such as nuclear accidents and chemical spills; and complex emergencies, including wars, forced migration, and humanitarian crises.

Disasters produce devastating impacts on environmental health and frequently trigger cascading processes referred to as the “environmental domino effect.” In particular, damage to infrastructure systems may result in contamination of drinking water supplies, disruption of sanitation services, and the emergence of secondary disasters such as infectious disease outbreaks. Therefore, essential environmental health components, including safe water supply, waste management, food safety, and vector control, constitute indispensable elements of disaster management.

Integrated Disaster Management primarily consists of two major phases: Risk Management and Crisis Management. Risk management encompasses pre-disaster mitigation and preparedness activities, including the development of risk maps, urban planning strategies, establishment of early warning systems, and community-based educational programs. Crisis management, on the other hand, includes disaster response and post-disaster recovery activities. Search and rescue operations, emergency medical services, and temporary shelter practices represent the core components of the response phase, whereas the recovery phase aims to enhance societal resilience.

Disaster processes also involve several psychosocial stages, including impact, heroism, honeymoon, disillusionment, and reconstruction phases. Consequently, effective disaster management requires strengthened multi-stakeholder coordination mechanisms and the integration of environmental health into the core of planning and decision-making processes.