The tests are being conducted jointly by FEMA, the FCC and local authorities to ensure the nation’s wireless emergency notification system is operational. The phone will make a loud sound and vibrate strongly when it receives a signal. The message on the screen will read: “This is a test of the National Wireless Emergency Alert System. “No action is required.”
However, citizens cannot reject this check. This is a requirement and all major carriers will send this to every device connected to their network. The test will last 30 minutes and they will only receive notification once.
Source: Ferra

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