Siren test in Vienna: Important warning on October 4th, 2025!

Siren test in Vienna: Important warning on October 4th, 2025!

Next Saturday, October 4, 2025, an important test of the sirens and the new warning system “AT-ALERT” will be carried out in Vienna. The city's 180 sirens will be heard between 12:00 and 12:45 p.m. During this time, the Viennese should develop a feel for the different civil defense signals and at the same time the technical functionality of the sirens should be checked. The city of Vienna is planning several siren tests on this day to make the population aware of the importance of the warning signals. The first siren test will start at 12 p.m. with a 15-second continuous sound, followed by further warning signals that will sound until 12:45 p.m. The signals are as follows:

• 12:00 Uhr: „Sirenenprobe“ – 15 Sekunden Dauerton
• 12:15 Uhr: „Warnung“ – 3 Minuten Dauerton
• 12:30 Uhr: „Alarm“ – 1 Minute auf- und abschwellender Heulton
• 12:45 Uhr: „Entwarnung“ – 1 Minute Dauerton

In contrast to other federal states, where the siren signals are tested weekly, this test in Vienna only takes place once a year. The aim of this exercise is not only to familiarize citizens with the signals, but also to guarantee technical performance. City technical departments are on site to check the audibility and condition of the sirens. Feedback on audibility can be submitted via a perception protocol. For the test, the siren telephone can be reached on Saturday from 11:30 a.m. to 1:30 p.m. on 01 4000 7524.

Integration of AT-ALERT

At the same time as the siren tests, the nationwide warning system “AT-ALERT” will also be activated. This enables authorities to send regional alerts quickly and efficiently via mobile networks, especially in cases of extreme weather, natural disasters or other threats. The first test message is triggered at 12:00 p.m. by the Federal Ministry of the Interior, followed by a second message between 12:45 and 1:00 p.m. from the respective federal state. Mobile phones that currently use common operating systems are capable of receiving these warning messages. Particularly important to know: the emergency alarm (Level 1) cannot be deactivated and should remain activated by all users, while warning levels of the lower category (Level 2) can be turned off.

Technology and security

Siren technology has evolved significantly in recent years. Great importance is placed on the choice of locations for the sirens in order to create the most effective siren network possible. Criteria such as sound pressure, buildings and ambient noise are crucial. The planning is carried out by specialists who also take weather and topographical aspects into account. Interestingly, many cities will take advantage of the opportunity to also use some sirens to alert fire departments and other emergency services. This is thanks to the close integration with modern communication media and Hörmann warning systems, which have international experience in the development of population warning systems.

In summary, the upcoming siren tests and the introduction of the “AT-ALERT” system represent essential steps towards improving security in Vienna. The public is warmly invited to actively participate and use the perception protocol to provide feedback. Civil protection is not only an issue for the authorities, but also requires the commitment of every individual.

For further information, those interested can view the updates and feedback at any time via the official platform of the City of Vienna: Press Vienna or for further research into siren technology HÖRMANN.