Date and time for national test of mobile alert system set in April

It's intended for life-threatening emergencies, but can be made silent if needed - as Harry Horton reports

An emergency alert will sound on most smartphones in the UK on Sunday April 23, the government has announced.

At 3pm on the day, phones will emit a siren and vibrate for 10 seconds in a nationwide test of a new public alert system.

The system is intended to be used in life-threatening situations including flooding and wildfires.

It is the first nationwide trial of the service, after pilots were conducted in Reading and East Suffolk.

The system is modelled on similar success schemes in the US, Canada, the Netherlands and Japan.

What will happen?

At 3pm, the message will be received on 4G and 5G mobile phones, along with sound and vibration for up to 10 seconds.

Phone users will be prompted to acknowledge the alert by swiping or clicking the "OK" message - just like for a 'low battery' warning or notification - before being able to continue using their device.

The sound and vibration will automatically stop after 10 seconds if no action is taken.

Chancellor of the Duchy of Lancaster Oliver Dowden said: "Getting this system operational with the national test means we have another tool in our toolkit to keep the public safe in life-threatening emergencies."

"It could be the sound that saves your life."

Can you opt out of the alerts?

People who do not wish to receive the alerts will be able to opt-out in their device settings.

But officials hope the life-saving potential of the messages means that users will keep them on.

According to the government, the system will be used "very rarely - only being sent where there is an immediate risk to people’s lives - so people may not receive an alert for months or years".

Planned to avoid sporting events

The test on St George’s Day coincides with major sporting events including the London Marathon and much-awaited football matches.

It had originally been planned to take place in the early evening but it was moved to avoid clashing with the London Marathon which begins at 9.30am that day, and the FA Cup semi-final which kicks off at 4.30pm.

The alert has been timed so that it doesn't disrupt the London Marathon. Credit: PA

The Premier League ties between Bournemouth and West Ham and Newcastle and Tottenham Hotspur will also kick off at 2pm - meaning the alarm will sound during the matches.

Officials said they have worked with the Football Association and the Marathon’s organisers to make sure the impact of the test will be limited.

National Fire Chiefs Council chairman Mark Hardingham said: "For 10 seconds the national test may be inconvenient for some, but please forgive us for the intrusion because, the next time you hear it - your life, and the life-saving actions of our emergency services, could depend on it."

Concerns for domestic abuse survivors

Domestic violence campaigners have warned the test could put people in danger by revealing the location of secret phones hidden away by those at risk.

The National Centre for Domestic Violence (NCDV) warned people with hidden second mobile phones to turn off the alerts to avoid revealing the location of their devices.

Its website features a step-by-step guide on how to turn off the alert.

NCDV’s Sharon Bryan said: "Hidden second mobiles are an emergency lifeline for victims and survivors living under the constant threat of abuse, or worse.

"This siren test may unexpectedly reveal their presence to abusers – with disastrous consequences.

"The government said it has been actively engaging with organisations working with vulnerable women and girls to ensure they are not adversely affected by the introduction of emergency alerts."

If you are concerned about the alert or need support, the following services are available:

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