Civil defense
protection of the citizens of a state (generally non-combatants) from military attack
Warning the population in case of a coming disaster
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Thunderbolt 1003
Federal Signal -
AL-8000
American Signal Corporation -
Flood siren -
SD-10
Federal Signal -
Warning-Signal of a German Siren
France
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Beginning of the alert: the sound warning is made of three sequences of sound going up and down lasting one minute, separated by a silence lasting five seconds. End of the alert: continuous signal of 380 Hz, lasting thirty seconds. -
In case of a signal generated by electronics, a cycle is made of a two-second rise from 300 Hz to 600 Hz, then a two-second decrease back to 300 Hz; in case of an electromechanical siren, a cycle is made of seven second where the motor is on (the sound rises to 380 Hz), then five seconds where the motor is shut down.
Switzerland
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General Alarm -
General Alarm
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Water Alarm -
Water Alarm
