ELI5: Explain Like I'm 5

Civil defense siren

A civil defense siren is a loud, warning sound that is used to alert people in a community about an emergency. It is usually a big, metal horn that is attached to a pole or a building’s roof.

These sirens are used in cases of emergencies like tornadoes, floods, fires, chemical spills, or even attacks from enemies. They are usually tested once a month by making a short sound or “blip” so that people are familiar with the sound of the siren in case of an emergency.

When an emergency occurs, a longer siren sound will be made, which means that people should take immediate action to protect themselves. This action can be different depending on the type of emergency or the instructions given by the local authorities, but usually, it means finding a safe place to stay and following the guidelines provided by the emergency services.

The civil defense siren can be heard from far away distances, which is why it is used to alert people in a large area about an emergency. It is an essential tool used by local authorities to protect people’s lives and minimize the risks associated with emergencies.