On Sunday 7 September at 3pm, the UK government will test the Emergency Alerts system on phones and tablets. Below is what you should expect to see and hear on the day. You will hear a loud siren-like sound like the one on the video, vibration, and a message will appear on the screen confirming that this is a test. The sound and vibration will last for about 10 seconds. This is just a test, and you will not need to take any further action. Find out more about these alerts 👉 gov.uk/alerts | Age