Overview

• Millions of compatible phones and tablets will vibrate, emit a ten-second siren-like sound and display a test message linking to GOV.UK
• Alerts are sent based on users’ current location without requiring location services or phone registration and they will override silent modes
• No action is required during the drill, which aims to validate system performance and public readiness
• The test fulfills the legal requirement for triennial drills and complements new investments in flood defences, telecom security and biosecurity centres
• Since its 2023 launch, the system has been deployed four times for real emergencies, including severe flooding and an unexploded World War II bomb warning