evacuation

Emergency evacuation is the urgent immediate egress or escape of people away from an area that contains an imminent threat, an on-going threat or a hazard to lives or property.
Examples range from the small scale evacuation of a building due to a storm or fire to the large scale evacuation of a city because of a flood, bombardment or approaching weather system. In situations involving hazardous materials or possible contamination, evacuees may be decontaminated prior to being transported out of the contaminated area.

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