by The government has launched a new emergency alert system that will send a siren-like alert to mobile phones.
The system will give government and emergency services the ability to send a message directly to mobile phones in the event of life-threatening situations. When your device receives the alert, it vibrates and emits a loud siren-like sound for up to 10 seconds.
The siren will be accompanied by a notification on your home screen, which you will need to acknowledge before you can use other features. The notification may include phone numbers or links to websites with additional information.
The new system, which will go live on Sunday, April 23, is expected to enable government and emergency services to quickly deliver urgent messages to nearly 90% of cell phones in a defined area. Any compatible device within range will receive the message.
Alerts can only be sent by authorized government and emergency service users. Alerts will always include details of the affected area and provide instructions on how best to respond, including links to gov.uk/alerts, which will provide additional information.
Messages will be broadcast from cell towers near the emergency, ensuring they are secure, free and one-way. Individuals’ privacy will not be affected as the alerts do not reveal anyone’s location or collect personal data.  
Members of the public should receive the alert approximately four to 10 seconds after it is sent. In contrast, SMS messages can take days to be sent when sent to the general population and will not be received by people outside the UK.
People who don’t want to receive these alerts can turn them off in their device settings. The system has already been successfully tested in East Suffolk and Reading, ahead of the planned national test. A survey of people after the tests revealed that 88% wanted to receive the alerts in the future.
Emergency alerts will be used very rarely since they will only be sent in the event of an immediate risk to people’s lives. Many people may not receive messages for months or years at a time. They will initially focus on the most severe weather incidents, including flooding and possible wildfires.
Announcing the launch of the system, Chancellor of the Duchy of Lancaster, MP Oliver Dowden, said: “We are strengthening our national resilience with a new system of emergency alerts, to deal with a wide range of threats – from floods to forest fires.
“It will revolutionize our ability to warn and inform people in immediate danger and help us keep people safe. As we’ve seen in the United States and elsewhere, the hum of a phone can save a life.
National Fire Chiefs Council Chairman Mark Hardingham also welcomed the launch of the system. “Along with all fire and rescue services across the country, I look forward to having emergency alerts available to help us do our jobs and to help communities in the event of an emergency.
“We have seen this type of system in action elsewhere in the world and we are looking forward to having the installation here in the UK – working with the fire services and our partners, we want this system to help us help you be as safe as you can if a crisis hits.
The United States, Canada, the Netherlands and Japan have all successfully deployed and used similar systems. The alerts have been widely credited with saving lives. However, the US state of Hawaii caused widespread panic on January 13, 2018 when it accidentally sent a warning alert of an incoming ballistic missile to TVs, radios and cell phones. Officials blamed poor communication during an exercise at the Hawaii Emergency Management Agency.
You can see what the alerts look like at gov.uk/alerts.
