Millions to receive emergency alert in ‘largest public safety exercise in British history’

Millions of smartphones on 4G and 5G networks across the UK will make a loud siren-like noise next month

Britain is set for the “largest public safety exercise in British history” next month as a mobile phone emergency alert test is rolled out.

Millions of smartphones on 4G and 5G networks across the UK will make a loud siren-like noise and vibrate at 3pm on 7 September.

The trial is part of the UK’s emergency alert system which is designed to warn people of disasters like storms or wildfires.

“This test will be one of the biggest public safety exercises in our nation’s history,” cabinet minister Pat McFadden said.

“From major storms to wildfires, this system could save your life in an emergency,” he said. “Just like the fire alarm in your house, it’s important we test the system so that we know it will work if we need it.”

A test of a new public alert system emitting a loud alarm on a mobile phone (Joe Giddens/PA) (PA Archive)

The first test was in April 2023. Since then, five alerts have been sent, including during major storms when lives were at risk, Mr McFadden said.

The government used the system during Storm Eowyn in January to warn people in Scotland and Northern Ireland about severe weather.

In December, around 3.5 million people in Wales and south-west England received an alert during Storm Darragh.

A warning was also triggered in February last year when an unexploded 500kg Second World War bomb was found in a Plymouth back garden.

The alert will read: “This is a test of Emergency Alerts, a UK government service that will warn you if there’s a life-threatening emergency nearby.

“You do not need to take any action. In a real emergency, follow the instructions in the alert to keep yourself and others safe. Find simple and effective advice on how to prepare for emergencies at gov.uk/prepare.”

Japan has similar emergency alert systems due to frequent earthquakes and tsunamis. The USA also has warning system in place.

In 2018, Hawaiian residents were mistakenly sent an alert telling them a ballistic missile was inbound as US president Donald Trump and North Korean leader Kim Jong Un exchanged nuclear threats.

Officials blamed miscommunication during a drill and the Hawaii Emergency Management Agency chief resigned over the blunder.