If you are sitting at home or work and hear the blare of sirens and alarms outside, don’t panic, it could be a test. To make sure its alert system is working, every year authorities in Switzerland conduct a siren test (Sirenentest) on the first Wednesday of February. With this in mind, here are all the details about the latest test, which will occur on February 5, 2025.

What you need to know about the siren test (Sirenentest) in Switzerland

To make sure that all 7.200 static and mobile sirens and alarms in Switzerland are in full working order, all of them will be tested from 1pm to 4.30pm on February 5, 2025. These devices are located across the country, from cities and towns to the peaks of mountains, so that people can be swiftly informed about an impending threat, national emergency or natural disaster.

Though it can be a shock or even scary for newcomers to hear their first-ever Sirenentest - especially if you come from a nation that does not have such a test - the key thing is not to panic. 

In the lead-up to the test, the government will notify the public through posters put up by Swiss councils and via television, radio and press announcements - 2025 also sees the launch of a cute, Pixar-esque information video. Anyone who wants to be the first to know can also check the status of the test itself using the AlertSwiss app on their mobile phones.

Swiss siren test in 2025

The 2025 edition of the siren test in Switzerland will begin at 1.30pm on February 5. From that time, the so-called general alarm signal will sound across the country. While they vary, generally the siren itself consists of a regularly ascending and descending tone. 

The first sirens will be tested for one minute at 1.30pm, and will be tested again after a two-minute silence. Local authorities reserve the right to keep testing the sirens until 2pm, but most systems will stop blaring after two tests.

For those who live near a select number of Swiss lakes, rivers and hydroelectric dams, the test will continue at 2pm, when the first of the water alert systems will sound. This signal consists of 12 low continuous tones lasting for 20 seconds, which is repeated at 10-second intervals. This test will conclude at 4.30pm at the latest.

What to do during the siren test

People across Switzerland are not expected to take any action or safety precautions during the siren test itself and are free to go about their business as usual. However, if the sirens do sound before or after the test, be sure to tune into the radio, TV or AlertSwiss app and follow the instructions given by the authorities.

After the 2025 run, the next siren test in Switzerland will take place on February 4, 2026.