California’s Earthquake Early Warning System was able to warn 2.2 million people via built-in smartphone capabilities and the MyShake app before an Oct. 25 earthquake.

In a press release, Gov. Gavin Newsom’s office explained that the warning system was able to give roughly 2.2 million Bay Area residents up 19 seconds of notice before the earthquake was felt. Nearly 2.1 million Android users received notifications due to built-in smartphone technology and an additionally 95,000 received notifications via the MyShake app.

“California continues to harness the power of science and technology to help keep our communities safe. When it comes to earthquakes, seconds can save lives. That’s why California continues to invest in new and emerging technologies to protect the most vulnerable among us,” said Gov. Newsom.

Following the earthquake, the Earthquake Early Warning System saw more than 108,000 new downloads of the MyShake App in a single day, which the governor’s office says is a record.

Earthquake warnings are based on a computerized program called ShakeAlert, which is operated by the United States Geological Survey (USGS) in partnership with California Office of Emergency Services (Cal OES). The program analyzes data from seismic networks in California, calculates preliminary magnitudes, and then estimates which areas will feel shaking.

The technology that powers the notification alerts is also used to automate protective actions such as slowing trains, opening firehouse doors, recalling elevators, shutting off water and gas valves, as well as closing bridges gates and notifying personnel in school and medical settings.

“While California has faced fires, drought and even a global pandemic, the single biggest threat we face to life and property in our state is a sizeable earthquake in one of our major population centers,” said Cal OES Director Mark Ghilarducci. “Tuesday was another important step in testing our technology but work still remains to prepare for the next big one.”

California’s Earthquake Early Warning System takes a two prong approach – a smartphone app and  traditional alert and warning delivery methods, such as Wireless Emergency Alerts. Due to the state’s approach, Californians can receive alerts through the free MyShake app for iPhone users, natively on Android smartphones, and through the text-based Wireless Emergency Alerts. MyShake app users can also use the HomeBase feature, which allows users to set a default location where they can receive earthquake early warning alerts, even if location services are temporarily down or turned off.

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