Don’t Be Alarmed if You Get This Sudden Alert on Your Phone on Oct. 4

No, you're not about to experience a natural disaster, zombie outbreak or apocalyptic asteroid collision — this is just a test!

On Wednesday, Oct. 4, the Federal Emergency Management Agency (FEMA) and Federal Communications Commission (FCC) will send a nationwide emergency alert test message to all televisions, cell phones, satellite devices and radios throughout the U.S.

This mandatory alert will test both WEA (messages sent to mobile devices) and EAS (messages sent to TV, cable, radio and satellite devices) capabilities. Both tests are scheduled to begin at approximately 2:20PM ET.

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The purpose of the alert test system is to confirm that the emergency alert systems are functioning properly in case of a national emergency.

The emergency alert test could be postponed in the event of widespread severe weather, or if a “significant event” occurs, in which case a backup test is scheduled for Oct. 11.

According to a FEMA press release, to help ensure the alerts are accessible to everyone, they will be accompanied by a unique tone as well as vibration on cellular devices.

What Will the Nationwide Emergency Test Alert Say and Sound Like?

The test message will be similar to regular monthly EAS test messages.

The audio message, which will be broadcast alongside a loud, blaring audio tone, will state:

This is a nationwide test of the Emergency Alert System, issued by the Federal Emergency Management Agency, covering the United States from 14:20 to 14:50 hours ET. This is only a test. No action is required by the public.”

Check out a similar alert that was distributed in 2011:

For cell phones, a similar message will appear via SMS alongside a loud audio tone.

The SMS text will read:

This is a test of the National Wireless Emergency Alert System. No action is needed.

The message will be received either in English or Spanish depending on the device's primary language setting.

How Long Will the Nationwide Emergency Test Alert Last?

The test alert should last for approximately 1 minute on television and radio.

Emergency test alerts sent to cell phones will be distributed within a 30-minute time span.