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Alerting the public

An emergency warning is issued when it is essential to warn the public of an imminent, immediate danger.

The main channels for emergency warnings are public warning sirens and speakers (used to sound public warning signals and to make spoken warnings), radio and TV, teletext (page 112, other public announcements on page 866), the Internet, speakers attached to vehicles and the print media.

Everybody should learn to recognize the alarm signals sounded with public warning sirens and know how to act. One of the emergencies announced with public warning sirens is hazardous gas in air.

What to do when you hear the public warning signal:

- Move indoors and stay there for the time being.
- Close all windows, doors and vents, and shut down all ventilation equipment.
- Avoid using the telephone so as to keep the lines free.
- To avoid further danger, do not leave the area unless advised to do so by the authorities.
- In a state of emergency, find shelter immediately.
- Turn on the radio and calmly wait for further instructions.

Public warning signal

The public warning signal can be either a minute-long undulating sound signal or a warning given by an authority. The rising and falling sequences of the sound signal take 7 seconds respectively. The public warning signal signifies an immediate threat to the general public.

All-clear signal   

The all-clear signal is an even one-minute sound signal. It signifies that the threat or danger has passed.


Emergency communication channels and outdoor emergency sirens are tested regularly. Sirens are tested at 12 noon on the first non-holiday Monday of each month. The siren test alarm is a continuous, even sound that lasts for 7 seconds. The test alarm requires no action. Calls to 112 must not be made on account of siren testing.  
The TV emergency communication system is tested at 11:20 on the first non-holiday Monday of each month. The radio emergency communication system is tested yearly on February 11.  

It is advisable to keep a battery-operated radio and spare batteries at home to be prepared for power outages.


15.05.2019 16:13