Emergency management (or disaster management) is the discipline dealing with and avoiding risks.[1] It is a discipline that involves preparing, supporting, and rebuilding society when natural or man-made disasters occur. Emergency management is the continuous process by which all individuals, groups, and communities manage hazards in an effort to avoid or ameliorate the impact of disasters resulting from the hazards. Actions taken depend in part on perceptions of risk of those exposed.[2] Effective emergency management relies on thorough integration of emergency plans at all levels of government and non-government involvement. Activities at each level (individual, group, community) affect the other levels. It is common to place the responsibility for governmental emergency management with the institutions for civil defense or within the conventional structure of the emergency services. In the private sector, emergency management is commonly referred to as business continuity management.
In the United States, the Constitution assigns the responsibility of public health and safety with state governments.[1] When an emergency or disaster occurs in a community, the resources of the local governments will be used first to manage the incident. With small-scale incidents, the response of local police, fire, and emergency medical services is usually sufficient. Once the resources of the local government are overwhelmed, the mayor of the city, town, or village will call upon the resources of the state for additional help. Likewise, the Federal government is called upon to act when the resources of local and state governments have been overwhelmed.[1] Governors of the affected states will request a disaster declaration from the President of the United States.