ShakeAlert earthquake early warning system launches

SEATTLE — Washington residents have new tool to help keep them safe when an earthquake strikes after the ShakeAlert Earthquake Early Warning System went live on Tuesday.

ShakeAlert will send residents an alert on their mobile phones, providing valuable seconds of warning to take cover before the shaking from an earthquake reaches their location.

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“The milestone we’re celebrating today has been 15 years in the making,” said David Applegate, acting director of the U.S. Geological Survey.

After a test of the system in March, the state’s emergency management division says preliminary results show that 60% of the people who signed up expecting an alert actually got one.

State officials say alerts might not come through if someone is watching a video on their phone. The success of the alerts also depended on the carrier.

The system uses a network of sensors that detect the start of an earthquake and calculates magnitude, location and the expected amount of shaking from earthquakes on the West Coast.

It sends the information in real-time to distributors that send out alerts to cellphones and the internet.

The system previously launched in California and Oregon.

>>ShakeAlert earthquake test reached 60% of people who expected to receive it

Washington state has the second-highest earthquake risk in the United States. It also has one of the highest tsunami risks.

The system is designed to give residents time to take cover in the event of an earthquake but it cannot predict when an earthquake will strike.

State officials say it’s important that people enable emergency alerts on their phones so they can receive the alerts.

Details on how to do that can be found here.

The Associated Press contributed to this story.