In a nationwide test of the UK’s emergency alert system, millions of mobile phones will vibrate and emit a siren sound on Sunday afternoon. The alert, lasting 10 seconds, is aimed at testing the system’s effectiveness and is scheduled to take place at 3pm. However, certain devices like older phones not connected to 4G or 5G networks and those that are turned off or in airplane mode will not receive the alert.
According to senior cabinet minister Pat McFadden, the system is crucial for warning people of imminent dangers, such as severe weather outbreaks. Since its first test in April 2023, the system has been utilized five times, most recently during Storm Éowyn in January when 4.5 million people received an alert.
A non-test use of the system occurred in February last year when a 500kg World War II bomb was found and safely removed from a backyard in Plymouth. The government has also provided guidelines for those who wish to opt out of the alerts, considering individuals who might be at risk due to domestic abuse.
During the first test of the system in April 2023, an estimated 7% of devices did not receive the alert, with issues traced to specific networks. However, these problems were resolved shortly after the test. The National Preparedness Commission emphasizes the importance of such tests for the UK’s readiness to handle various threats, including extreme weather and national security challenges.
Source: https://www.theguardian.com/society/2025/sep/06/uk-mobile-phones-test-emergency-alert-sunday
