Air raid warning sirens at noon on Monday are a planned test

The public warning sirens that will go off Monday at noon are part of a regularly scheduled test, and are not related to any military activity, like the war in Ukraine, according to an extra reminder issued by the government. All 4,278 sirens in the Netherlands are tested at noon on the first Monday of every month so that the public can recognize the sound in the event of an actual disaster. 

The siren test lasts one minute and 26 seconds. If people do not hear the siren test, they are advised to report this to the fire brigade in their local security region.

In the case of an actual emergency, sirens would sound for a longer duration, and several times in succession. People are then instructed to go inside immediately, close their doors and windows and switch off electronic ventilation when they hear this sound. In such a case, more information would be provided via radio or television from regional emergency broadcasters, or from the national NL-Alert warning system, which delivers messages directly to mobile phones and public video screens.

Siren tests do not go off during national commemorations or holidays. For example, sirens are not tested in June because the first Monday falls on Pentecost Monday.