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Warning of the population

How are you warned in case of danger? What is the significance of siren signals? And how do you behave in an emergency? Here you will find the answers.

  1. Sirens
  2. Loudspeaker announcements by warning vehicles
  3. Radio warning and announcements, information telephone
  4. Warning apps
  5. Cell Broadcast (messages similar to an SMS)
  6. Test alarm
  7. Behavior in case of emergency

In the event of an imminent danger, e.g. a leakage of hazardous substances, major fires, severe storms, floods, a prolonged failure of electricity, water or gas, or a terrorist attack, the population is warned by a modular warning system. From this moment on, the population's ability to help itself is called for, depending on the damage event.


Sirens are an important component of the modular warning system. Today, there are 57 modern high-power sirens in the city area. In case of imminent danger for the population, the sirens warn with the following tone:

Warning tone: one-minute rising and falling wailing tone

This signal is repeated several times to improve the chance that the signal is perceived by all.

Listen to warning signal
Listen to warning signal

All clear: one-minute continuous tone

Listen to all clear signal tone
Listen to all clear signal tone

Loudspeaker announcements by warning vehicles

Mobile warning and public address system of the Bonn Fire Department.

In addition, targeted information of the population can be provided via loudspeaker announcements by means of specially equipped vehicles of the fire department and/or police. The Bonn Fire Department maintains 21 "mobile warning loudspeaker systems" for this purpose.

Radio warning and announcements, information telephone

In the event of a siren alarm, specific information and announcements of behavioral measures are made promptly via the radio stations. The control center of the Bonn Fire Department can make warning announcements directly and broadcast them via the Radio Bonn-Rhein-Sieg station.

In addition, an information telephone can be set up with the number 0228 71 71. Information and instructions for action are available via recorded message. Alternatively, if necessary, individual advice can be arranged via hotline.

Up-to-date information can also be found on the Internet in this case: At (opens in a new tab), you will receive information or instructions for action via a pop-up window, depending on the damage situation. In addition, the city of Bonn provides information on its social media channels in the event of a disaster.

Warning apps

Official warnings are also distributed as push messages via smartphone apps. The official warning app of the federal government is  NINA (opens in a new tab).

Other warning apps include  BIWAPP (opens in a new tab) and  KATWARN (opens in a new tab). For official weather warnings, the  WarnWetter app (opens in a new tab) of the German Weather Service is available.

Cell Broadcast (messages similar to an SMS)

During the nationwide warning day on December 8, 2022, the Cell Broadcast warning channel was tested for the first time. This system can be used to send warning messages to all mobile terminals located in a specific section of the cellular network. Cell Broadcast began operating on February 23, 2023.

Test alarm

The functionality of the modular warning system is regularly checked by nationwide and statewide test alarms. The dates are announced in good time via the local media. Detailed information on the nationwide warning day is provided by the Federal Office of Civil Protection and Disaster Assistance (BBK) on  its own website. (opens in a new tab)

Behavior in case of emergency

Switch on the radio and select the local radio station Radio Bonn-Rhein-Sieg (97.8 MHz) or WDR 2. These stations will provide you with information about the damage event and appropriate behavior. The stations also provide information on their websites.

As a general rule, please observe the following general precautions and instructions:

  • Seek out closed rooms, stay in the building and, if necessary, pick up passers-by.
  • Close windows and doors and turn off air conditioning or ventilation.
  • Remain calm and follow the instructions of the emergency services.
  • Do not use the telephone or use it only in an extreme emergency.
  • Dial the emergency numbers 110 and 112 only in an emergency.
  • In the event of serious damage, the information telephone 0228 71 71 can be used to report damage.