warning notification

An emergency population warning or public warning system is a method whereby local, regional, or national authorities can contact or notify members of the public to warn them of an impending emergency. These warnings may be necessary for a number of reasons, including:

Weather emergencies such as cyclones, flooding, tornadoes, avalanches and severe weather.
Geological disasters such as earthquakes, landslides, volcanic eruptions, and tsunamis.
Industrial disasters such as the release of toxic gas or contamination of river water.
Radiological disasters such as a nuclear plant disaster.
Medical emergencies such as an outbreak of a fast-moving infectious disease or pandemic.
Warfare such as air raids or acts of terrorism.
Other events, such as prison escapes, abducted children or emergency telephone number outages.
Warnings are often disseminated during urgent events such as evacuations or where a severe threat to life is expected.
Common alerting methods include sirens, radio, television, local media, telephone, SMS and Cell Broadcast.

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